Gold Book Terms
'A' value A-factor \(A\)ab initio calculations ab initio quantum mechanical methods abatement in atmospheric chemistryabeo- abiological abiotic abiotic transformation absolute activation analysis absolute activity \(\lambda\)absolute configuration absolute counting in radioanalytical chemistryabsolute electrode potential absolute full energy peak efficiency absolute lethal concentration \(\text{LC}_{100}\)absolute lethal dose \(\text{LD}_{100}\)absolute photopeak efficiency absolute preconcentration in trace analysisabsorbance matching in spectrochemical analysisabsorbance \(A\)absorbed (spectral) photon flux density absorbed (spectral) radiant power density absorbed dose of a substanceabsorbed dose \(D\) of radiationabsorbed electron coefficient in in situ microanalysisabsorbed electrons in in situ microanalysisabsorber absorptance \(\alpha\)absorption absorption coefficient absorption coefficient in biologyabsorption cross-section \(\sigma\)absorption factor absorption intensity absorption line absorption pathlength of a sample cellabsorption spectrum absorptivity abstraction abstraction process in catalysisabundance sensitivity in mass spectrometryac accelerating voltage scan \(\text{V}\) in mass spectrometryacceleration energy in in situ microanalysisacceleration of free fall \(g\)acceleration \(a\)accelerator in solvent extractionacceptable daily intake acceptor number \(\text{AN}\)accommodation coefficient accretion in atmospheric chemistryaccuracy of a measuring instrumentaccuracy of measurementacenes acetals acetogenins acetonides acetylene black acetylenes acetylides Acheson graphite achiral achirotopic aci-nitro compounds acid acid anhydrides acid deposition in atmospheric chemistryacid rain in atmospheric chemistryacid thioanhydrides acid-labile sulfur acid–base indicator acid–base titration acidimetric titration acidity of a mediumacidity constant acidity function acidosis actinic actinic flux \(S_{\lambda}\)actinism actinometer action spectrum activated adsorption process activated carbon activated charcoal activated complex activation activation analysis (nuclear) activation cross-section activation energy activation in electrochemical corrosionactivation in radiochemistryactivation reaction activator active centre active medium active metal in electrochemical corrosionactive site in heterogeneous catalysisactive solid active species active state in electrochemical corrosionactive transport in biologyactivity activity \(a\)activity coefficient \(f\),\(\gamma \)activity \(A\) of a radioactive materialacute toxicity acyl anions acyl carbenes acyl cations acyl groups acyl halides acyl radicals acyl shift (1,2-, 1,3-, photochemical) acyl species acylals acylium ions acyloins acyloxyl radicals added hydrogen addend addition addition reaction additive additive name additivity of mass spectraadditivity principle adduct adduct ion in mass spectrometryadhesional wetting adiabatic adiabatic electron transfer adiabatic ionization in mass spectrometryadiabatic lapse rate in atmospheric chemistryadiabatic photoreaction adiabatic transition-state theory adiabatic treatments of reaction rates adjacent re-entry model in polymer crystalsadjusted retention volume adjuvant in immunologyADMR adsorbate adsorbent adsorber adsorption adsorption capacity adsorption chromatography adsorption complex adsorption current adsorption hysteresis adsorption indicator adsorption isobar adsorption isostere adsorption isotherm in chromatographyadsorptive advancement advection in atmospheric chemistryadverse effect aeration in atmospheric chemistryaerobe aerobic aerobic conditions aerogel aerometer in atmospheric chemistryaerometric measurement in atmospheric chemistryaerosol aerosol hydrolysis affine chain behaviour affinity chromatography affinity of reaction \(A\)after mass analysis in mass spectrometryageing of precipitate of precipitateagglomerate in catalysisagglomerate in polymer scienceagglomeration (except in polymer science) agglomeration in polymer scienceagglutination aggregate in catalysisaggregation (except in polymer science) aging of a polymeraglycon agonist agostic agostic interaction agranular carbon air contaminant in atmospheric chemistryair mass in atmospheric chemistryair monitoring station in atmospheric chemistryair pollutant air pollution air pollution index air pollution survey in atmospheric chemistryair quality characteristic in atmospheric chemistryair resource management in atmospheric chemistryair sampling network in atmospheric chemistryair-lift bioreactor Aitken particles albedo albumin alcogel alcoholates alcohols alcoholysis aldaric acids aldazines aldehydes aldimines alditols aldoketoses aldonic acids aldoses aldoximes alert levels in atmospheric chemistryalicyclic compounds aliphatic compounds aliquot in analytical chemistryalkalimetric titration alkaloids alkalosis alkanes alkanium ions alkene photocycloaddition alkene photodimerization alkene photoisomerization alkene photorearrangement alkenes alkoxides alkoxyamines alkyl groups alkyl radicals alkylenes alkylidene groups alkylideneamino carbenes alkylideneaminoxyl radicals alkylideneaminyl radicals alkylidenes alkylidynes alkynes allele allenes allo- in amino-acid nomenclatureallometric allosteric enzymes allostery allotriomorphic transition allotropes allotropic transition allylic groups allylic intermediates allylic substitution reaction alternancy symmetry alternant alternating copolymer alternating copolymerization alternating current alternating voltage altocumulus cloud in atmospheric chemistryaltostratus cloud in atmospheric chemistryAM 0 sunlight AM 1 sunlight amalgam lamp ambident ambient air in atmospheric chemistryambient air quality in atmospheric chemistryambo Ames/salmonella test amic acids amide hydrazones amide oximes amides amidines amidium ions amidrazones aminals amine imides amine imines amine oxides amine ylides amines aminimides aminium ions aminiumyl radical ions amino radicals amino sugars amino-acid residue in a polypeptideaminonitrenes aminooxyl radicals aminoxides aminoxyl radicals aminyl oxides aminyl radicals aminylenes aminylium ions ammonium compounds ammonium imines ammonium ylides ammoniumyl radical ions amorphous carbon amount concentration \(c\)amount fraction x (y for gaseous mixtures) amount of substance \(n\)amount-of-substance concentration amount-of-substance fraction \(x\)ampere \(\text{A}\)amperometric detection method in electrochemical analysisamphipathic amphiphilic amphiprotic (solvent) ampholytes ampholytic polymer amphoteric amplification reaction amplitude of alternating current amplitude of alternating voltage anabolism anaerobe anaerobic anaesthetic analgesic analogue metabolism analogue to digital converter (pulse) analyte analytical function analytical instrument analytical intercomparison analytical portion analytical pyrolysis analytical quality control analytical radiochemistry analytical sample analytical solution analytical solution calorimetry analytical unit anation anchimeric assistance aneroid barometer Anger camera angle angle of observation angle of optical rotation \(\alpha\)angle strain angular distribution angular frequency \(\omega\)angular momentum \(L\)angular overlap model anhydrides anhydro bases anilides anils anion anion exchange anion exchanger anion radical anion-exchange polymer anionic polymer anionic polymerization anionotropic rearrangement anisometric anisotropy annelation annihilation in photochemistryannulation annulenes annulenylidenes anode anodic transfer coefficient anomeric effect anomers ansa compounds antagonism antagonist antarafacial anthelmint(h)ic anthocyanidins anthocyanins anti anti-Compton γ-ray spectrometer anti-Hammond effect anti-Markownikoff addition anti-Stokes shift anti-Stokes type radiation (fluorescence) anti-thixotropy antiaromatic compounds antiaromaticity antibiotic antibody antibonding molecular orbital anticholinergic anticircular elution in planar chromatographyanticlinal anticlined structures in polymersanticodon anticyclone in atmospheric chemistryantiferroelectric transition antiferromagnetic transition antigen antihelminth antimetabolite antimony–xenon lamp (arc) antimycotic antiparticle antiperiplanar antipodes antiprismo- antiresistant antiserum antisymmetry principle ap apex apex current apex potential aphicide apical (basal, equatorial) apicophilicity apo- in carotenoid nomenclatureapoenzyme apoprotein apoptosis apparent (quantity) apparent lifetime apparent viscosity of a liquidappearance energy appearance potential appearance temperature \(T_{\text{app}}\) in electrothermal atomizationapplied potential aprotic (solvent) aquagel aquation arachno- Archibald's method area of an electrode-solution interfacearea of interface area viscosity areic arene epoxides arene oxides arenes arenium ions arenols arenonium ions argon ion laser arithmetic mean aromatic aromatic photocycloaddition aromaticity arrester in atmospheric chemistryArrhenius A factor \(A\)Arrhenius energy of activation Arrhenius equation arsanes arsanylidenes arsanylium ions arsenides arsine oxides arsines arsinic acids arsinidenes arsinous acids arsonic acids arsonium compounds arsonous acids arsoranes artificial graphite artificial neural networks artificial radioactivity aryl cations aryl groups arylene groups aryne ascending elution in planar chromatographyash in atmospheric chemistryashing in analysisaspirator assay assay kit association association reaction in mass spectrometryassociative desorption associative ionization in mass spectrometryassociative surface reaction asym- asymmetric asymmetric carbon atom asymmetric centre asymmetric destruction asymmetric film asymmetric induction asymmetric membrane asymmetric photochemistry asymmetric synthesis asymmetric transformation asymmetry asymmetry potential of a glass electrodeatactic macromolecule atactic polymer atmosphere atmosphere of the earthatmospheric pressure ionization in mass spectrometryatom atom-atom polarizability atom-bond polarizability atom–molecule complex mechanism atomic charge atomic fluorescence atomic laser atomic mass constant atomic mass \(m_{\text{a}}\)atomic mass unit atomic number \(Z\)atomic orbital \(\psi\),\(\varphi\),\(\chi\)atomic ring-sector atomic spectral lines atomic symbol atomic units atomic weight atomization in analytical flame spectroscopyatomization surface temperature \(T_{\text{s}}\) in electrothermal atomizationatomize atomizer in analytical flame spectroscopyatropisomers attachment attenuance filter attenuance \(D\)attenuation attenuation coefficient atto attractive potential-energy surface attractive–mixed–repulsive classification attributable risk aufbau principle Auger effect Auger electron Auger electron spectroscopy Auger electron yield Auger yield autacoid auto-ionization in mass spectrometryautocatalytic reaction automation in analysisautomerization autophobicity autopoisoning in catalysisautoprotolysis autoprotolysis constant autoradiograph autoradiolysis auxiliary electrode auxochrome auxotrophy avalanche photodiode average current density average degree of polymerization average life in nuclear chemistryaverage rate of flow in polarographyAvogadro constant \(N_{\text{A}}\),\(L\)avoided crossing of potential-energy surfacesAvrami equation axial (equatorial) axial chirality axialite in polymer crystalsaxis of chirality axis of helicity aza-di-π-methane rearrangement azacarbenes azamines azanes azenes azides azimines azines azinic acids azlactones azo compounds azo imides azo ylides azomethine imides azomethine oxides azomethine ylides azomethines azonic acids azoxy compounds azylenes α (alpha), β (beta) α-addition α-cleavage α-decay α-effect α-elimination α-oxo carbenes α-particle π-adduct σ-adduct
back donation back electron transfer back extraction back scatter coefficient in in situ microanalysisback scattered electrons in in situ microanalysisback washing backbone backflush background concentration in atmospheric chemistrybackground mass spectrum background of a radiation measuring devicebackground radiation backscatter backscattering spectroscopy Baeyer strain baffle chamber in atmospheric chemistrybag filter in atmospheric chemistrybaghouse in atmospheric chemistryBainite transition baking in carbon chemistryBaldwin's rules band spectra bandgap energy \(E_{\text{g}}\)bandpass filter bar barbiturates barn Barton reaction basal base base electrolyte base kind of quantity base pairing base peak in mass spectrometrybase quantity base unit of measurementbaseline concentration in atmospheric chemistrybaseline error in spectrochemical analysisbaseline in chromatographybasicity basicity function basis function basis set batch in analytical chemistrybatch injection calorimetry batch operation in analysisbatch reactor Bates–Guggenheim convention bathochromic shift (effect) bead-rod model bead-spring model beam current in in situ microanalysisbeam diameter in in situ microanalysisbeam-gas experiments becquerel bed volume in chromatographyBeer–Lambert law before mass analysis in mass spectrometryBell–Evans–Polanyi principle benchmark dose (BMD) and lower effective dose (LED) bending of energy bands Bent's rule benzenium ions benzenonium ions benzylic groups benzylic intermediates benzynes Berry pseudorotation betaines betweenanenes bias bias error biased linear pulse amplifier bicycle rearrangement bicycle-pedal (BP) mechanism bifunctional catalysis bilayer bimodal distribution bimodal network bimolecular binder binder coke binder in chromatographybinding energy binding site Bingham flow bioassay bioavailability (general) bioavailabilty in pharmacokineticsbiocatalyst biochemical (biological) oxygen demand biochip bioconjugate bioconversion biodegradable polymer biodegradation bioelectronics bioisostere biological effect monitoring biological exposure index biological half life biological monitoring biological tolerance values for working materials bioluminescence biomarker biomass biomimetic biopolymers bioreactor biosensor biosphere in atmospheric chemistrybiosynthesis biotechnology biotransformation biphotonic excitation biphotonic process bipolarons bipolymer biradical bisecting conformation bismuthanes bismuthines bisphenols bivane in atmospheric chemistryblack film blank value in analysisblaze-angle in spectrochemical analysisbleaching in photochemistryblock block copolymer block macromolecule block polymer blotting in biotechnologyblowdown in atmospheric chemistryblue shift boat Bodenstein approximation body burden bohr Bohr magneton Bohr radius bolometer Boltzmann constant \(k\)bomb-digestion in spectrochemical analysisbond bond dissociation bond energy bond energy in theoretical chemistrybond length bond migration bond number bond opposition strain bond orbital bond order bond order \(p_{\text{rs}}\)bond ring-sector bond-dissociation energy in theoretical chemistrybond-dissociation energy \(D\)bond-energy-bond-order method bonded phase in chromatographybonding molecular orbital bonding number boranes boranylidenes borderline mechanism borenes borinic acids Born–Oppenheimer (BO) approximation boronic acids borylenes boson bound fraction in radioanalytical chemistryboundary layer in atmospheric chemistrybowsprit (flagpole) branch (side chain, pendant chain) in polymersbranch point in polymersbranch unit in polymersbranched chain in polymersbranched polymer in polymersbranching chain reaction branching decay branching fraction branching index branching plane branching ratio break of a foambreak of an emulsionBredt's rule breeching in atmospheric chemistrybreeze in atmospheric chemistryBremsstrahlung Brewster angle \(\theta_{\text{B}}\)bridge bridge index bridge solution in pH measurementbridged carbocation bridgehead bridging ligand brightness brightness of a laser dyebromohydrins bromonium ions Brooks and Taylor structure Brownian motion Brønsted acid Brønsted base Brønsted relation brush macromolecule bubble column bubbler in atmospheric chemistrybuffer-addition technique in analytical flame spectroscopybulk concentration in electroanalysisbulk mesophase bulk rheology bulk sample bulk strain Bunnett–Olsen equations Bunsen burner Bunte salts burn-up burn-up fraction burning tension of an electrical arcburning velocity \(\nu_{\text{b}}\) of a flame frontbypass injector in gas chromatographyβ (beta) β-cleavage in mass spectrometryβ-decay β-particle π-bond σ-bond
(chain) conformational repeating unit of a polymerC-terminal residue in a polypeptideC. I. P. system cadium–helium laser cage cage compound cage effect Cahn–Ingold–Prelog system calcination calcined coke calibration component calibration curve calibration function in analysiscalibration gas mixture in atmospheric chemistrycalibration in analysiscalibration material in analysiscalibration mixture in analysiscalibration sample in analysiscalixarenes calorie calorimetric titration calorimetry candela \(\text{cd}\)canonical form canonical rate constant canonical variational transition-state theory capacitance hygrometer capacitance \(C\) of a plate capacitorcapillary column in chromatographycapillary condensation captodative effect capture capture cross-section capture γ-radiation carbaboranes carbamates carbanion carbena carbene analogues carbene metal complexes carbene radical anions carbene radical cations carbenes carbenium centre carbenium ion carbenoids carbinolamines carbinols carbinyl cations carbo-reduction carbocation carbocyclic compounds carbodiimides carbohydrates carbon carbon artifact carbon black carbon cenospheres carbon cloth carbon dioxide laser carbon electrode carbon felt carbon fibre carbon fibre fabrics carbon fibres type HM carbon fibres type HT carbon fibres type IM carbon fibres type LM carbon fibres type UHM carbon loading of the packing materialcarbon material carbon mix carbon whiskers carbon–carbon composite carbonaceous mesophase carbonitriles carbonium ion carbonization carbonyl compounds carbonyl imides carbonyl imines carbonyl oxides carbonyl ylides carboranes carboxamides carboxamidines carboxylic acids carbylamines carbyne metal complexes carbynes carbynium ions carotenes carotenoids carrier carrier atom in organic reaction mechanismscarrier gas carrier in radioanalytical chemistrycarrier protein carrier-free carry-over carry-over effect cascade impactor catabolism catabolite repression catalase catalymetric titration catalysed rate of reaction \(\xi_{\text{cat}}\)catalysis catalysis law catalyst catalyst ageing catalyst deactivation catalyst decay catalyst in solvent extractioncatalytic activity concentration \(b\)catalytic activity content \(^{z}/_{m}\)catalytic activity fraction of an isozymecatalytic activity \(z\) of an enzymecatalytic coefficient catalytic concentration catalytic content catalytic cracking catalytic current catalytic current, limiting catalytic dehydrocyclization catalytic domain of a polypeptide of a polypeptidecatalytic fraction catalytic graphitization catalytic hydrocracking catalytic hydrodesulfurization catalytic hydrogenolysis catalytic methanation catalytic reforming catalytic thermometric titration cataphoresis catecholamines catena- catenanes cathode cathodic transfer coefficient \(\alpha_{\text{c}}\)cation cation exchange cation exchanger cation radical cation-exchange polymer cationic polymer cationic polymerization cationotropic rearrangement cationotropy cavitands cavity dumping in photochemistrycDNA ceiling value \(\text{CV}\)ceilometer in atmospheric chemistrycell constant of a conductivity cellcell error in spectrochemical analysiscell line Celsius temperature \(t\),\(\theta\)centi central atom centre of a Mössbauer spectrumcentre of chirality centrifugal acceleration \(a_{\text{rot}}\)centrifugal barrier centrifugal flow centrifugal force \(F_{\text{rot}}\)centrifugal radius \(r\)cephalins cephalosporins cephams cephems ceramer ceramic ceramic filter ceramic precursor ceramic yield ceramic-reinforced polymer ceramization Cerenkov detector Cerenkov effect Cerenkov radiation chain axis of a polymerchain branching chain carrier chain entanglement chain fission yield chain folding in polymer crystalschain in polymerschain initiation chain length \(\delta\)chain polymerization chain reaction chain scission of a polymerchain transfer chain-ending step chain-orientational disorder in polymer crystalschain-propagating reaction chain-termination reaction chair–chair interconversion chair, boat, twist chalcones chamber saturation in gas chromatographychange of a quantity change ratio of a quantity channel channel black channel photomultiplier tube chaperon char characteristic group in organic nomenclaturecharacteristic in analytical chemistrycharacteristic length in thin filmscharacteristic mass for integrated absorbance \(m_{0}\) in electrothermal atomizationcharacteristic mass for peak absorption \(m_{\text{p}}\) in electrothermal atomizationcharacteristic mass \(m_{\text{c}}\) in electrothermal atomizationcharacteristic potential characteristic ratio in polymerscharacteristic scale in thin filmscharacteristic X-radiation characteristic X-ray emission charcoal charge charge density \(\rho\)charge hopping charge number in inorganic nomenclaturecharge number \(n\),\(\nu _{\text{e}}\),\(z\) of a cell reactioncharge number \(z\)charge population charge recombination charge separation charge shift charge-transfer transition to solvent charge-exchange ionization in mass spectrometrycharge-exchange reaction charge-inversion mass spectrum charge-permutation reaction charge-stripping reaction charge-transfer (CT) state charge-transfer (CT) transition charge-transfer adsorption charge-transfer complex charge-transfer device in radiation detectioncharge-transfer reaction in mass spectrometrycharge-transfer step of an electrode reactioncharring chelate chelating polymer chelation chelatometric titration cheletropic reaction chelotropic reaction chemi-ionization in mass spectrometrychemical actinometer chemical activation chemical adsorption chemical amount chemical amplification chemical bond chemical decomposition chemical diffusion chemical dosimeter chemical element chemical equilibrium chemical flux \(\varphi\)chemical functionality chemical induction (coupling) chemical ionization in mass spectrometrychemical isotope exchange chemical laser chemical measurement process chemical modification chemical oxygen demand chemical potential \(\mu _{\text{B}}\)chemical reaction chemical reaction equation chemical relaxation chemical shift in photoelectron and Auger spectrachemical shift \(\delta\) in NMRchemical species chemical species of an elementchemical substance chemical vapour generation in spectrochemical analysischemical yield chemically bonded hybrid (material) chemically induced dynamic electron polarization chemically induced dynamic nuclear polarization chemically initiated electron exchange luminescence chemiexcitation chemiflux chemiluminescence chemiluminescence analyser chemiluminescent methods of detection in analysischemisorption chemometrics chemoselectivity (chemoselective) chemospecificity chemostat chimney effect in atmospheric chemistrychiral chiral mobile phase chiral selector chiral stationary phase in liquid chromatographychirality chirality axis chirality centre chirality element chirality plane chirality sense chiroptic/chiroptical chirotopic chloramines chlorocarbons chlorohydrins chloronium ions cholesteric phase chromatogram chromatograph (noun) chromatograph (verb) chromatographic detector chromatography chromophore chromosome chronic toxicity Chemically Induced Dynamic Electron Polarization Chemically Induced Dynamic Nuclear Polarization Chemically Initiated Electron Exchange Luminescence cine-substitution CIP priority circular development circular dichroism circular elution circular frequency cis conformation in polymerscis- in inorganic nomenclaturecis-fused cis-trans isomers cis, trans cisoid conformation cistactic polymer class (a) metal ion class (b) metal ion class of helix in polymersclathrates clausius clay hybrid clean surface clean up in spectrochemical analysisclearance in renal toxicologyclearance \(^{\Delta V}/_{\Delta t}\)clearing point clinal CLOGP values clone closed film closed shell molecular systems closed system in spectrochemical analysiscloso- cloud in atmospheric chemistrycluster cluster analysis cluster ion in mass spectrometryco-ions co-oligomer co-oligomerization co-solvency in polymersCO2 laser coacervation coagulation in colloid chemistrycoal tar pitch coal-derived pitch coke coalescence in colloid chemistrycoalification cobalamines codon coefficient coefficient of haze \(\text{COH}\) in atmospheric chemistrycoenzyme coextraction cofactors coherence length \(\zeta\) in thin filmscoherent (derived) unit of measurementcoherent radiation coherent scattering coherent source in spectrochemistrycoherent structure coherent system of units of measurement of measurementcoincidence circuit coincidence resolving time coke coke breeze coking col cold neutrons collection collection efficiency in atmospheric chemistrycollection gas flow system in spectrochemical analysiscollector collector in atmospheric chemistrycolligation collimation collimator collinear reaction collision complex collision cross-section \(\sigma\)collision density \(Z_{\text{AA}}\)collision diameter \(d\)collision efficiency \(B_{\text{c}}\)collision frequency \(z_{\text{A}}(\text{A})\)collision number collision theory collision-induced dissociation in mass spectrometrycollisional activation in mass spectrometrycollisional broadening of a spectral linecollisional excitation in mass spectrometrycolloid colloid osmotic pressure colloidal colloidal carbon colloidal dispersion colloidal electrolyte colloidal gel colloidal network colloidal processing colloidal suspension colloidally stable color scale colorimeter colour indicator colourability column chromatography column in chromatographycolumn volume \(V_{\text{c}}\) in chromatographycomb macromolecule comb polymer combination electrode combined sample combustion gas commensurate–incommensurate transition common black film common-ion effect (on rates) communities compact layer in electrochemistrycomparative molecular field analysis comparator in radioanalytical chemistrycompartmental analysis compatible polymer blend compensation effect compensation in catalysiscompensation in stereochemistrycompetition competitive binding assay competitive inhibition of catalysiscomplementary binding sites complementary DNA complete active space self-consistent field complete active space self-consistent field second-order perturbation theory complex complex coacervation complex mechanism complex reaction complex-mode reaction complexometric titration component composite composite mechanism composite membrane composite reaction composite sample composition of pure air in atmospheric chemistrycompositional heterogeneity of polymerscompressibility factor compression factor \(Z\)comproportionation Compton effect Compton electron Compton scattering computational chemistry computational photochemistry computer-assisted drug design computer-assisted molecular design computer-assisted molecular modeling concave isotherm in chromatographyconcentrated phase in polymer chemistryconcentration concentration depolarization concentration distribution ratio \(D_{\text{c}}\) in chromatographyconcentration factor in solvent extractionconcentration gradient \(\text{grad}\: C\)concentration in experimental surface (or surface concentration) concentration overpotential concentration thermometric technique in enthalpimetric analysisconcentration-cell corrosion concentration-sensitive detector in chromatographyconcerted process concerted reaction condensation in atmospheric chemistrycondensation nuclei in atmospheric chemistrycondensation polymerization condensation reaction condensative chain polymerization conditional (formal) potential conditional rate constant of an electrode reaction conditioning in solvent extractionconductance \(G\)conducting polymer conducting polymer composite conduction band conductivity \(\gamma\),\(\sigma \)confidence level confidence limits (about the mean) configuration (electronic) configuration (stereochemical) configuration interaction configurational base unit in polymersconfigurational disorder in polymersconfigurational homosequence in polymersconfigurational repeating unit in polymersconfigurational sequence in polymersconfigurational unit in polymersconfined atomizer conformation conformational analysis conformational analysis in drug designconformational disorder in polymersconformational repeating unit of a polymer conformer congener conglomerate congruent transition conical intersection coning and quartering in analytical chemistryconjugate acid–base pair conjugate solutions conjugated system conjugation conjugation in gene technologyconjugation labelling in radioanalytical chemistryconjugative mechanism conjunctive name connectivity connectivity in polymer chemistryconrotatory consecutive reactions consecutive steps conservation of orbital symmetry consignment in analytical chemistryconsistency consolute point constituent constitution constitutional heterogeneity of polymersconstitutional homosequence constitutional isomerism constitutional repeating unit in polymersconstitutional sequence in polymersconstitutional unit constitutive enzymes contact angle contact corrosion contact ion pair contact potential difference contamination content continuity inversion in solvent extractioncontinuous analyser continuous bed packing in liquid chromatographycontinuous flow continuous flow enthalpimetry continuous indication analyser continuous measuring cell continuous operation in analysiscontinuous precipitation continuous transition continuous wave (CW) laser continuous-flow cell in spectrochemical analysiscontinuously curved chain in polymerscontour length in polymerscontributing structure control material in analysiscontrol sample in analysiscontrolled atmosphere in atmospheric chemistryconvection (as applied to air motion) convenience sample conventional transition-state theory conventional true value conversion cross-section conversion electron conversion spectrum convex isotherm in chromatographycooperative transition cooperativity coordinate covalence coordinate link coordination coordination entity coordination number coordination polyhedron coordinatively saturated complex coordinatively unsaturated complex copolymer copolymer micelle copolymerization copper vapour laser coprecipitation copy number in biotechnologycore atom in organic reaction mechanismscoronands corrected emission spectrum corrected excitation spectrum corrected retention volume in gas chromatographycorrelation analysis correlation coefficient correlation diagram correlation energy corrinoids (cobalamines, corphyrins, corrins, vitamin B12 compounds) corrosion corrosion cell corrosion current corrosion potential \(E_{\text{cor}}\)corrosion rate cosolvent cosphere cotectic coulomb \(\text{C}\)coulomb integral \(H_{\text{rr}}\)Coulomb repulsion coulometric detection method in electrochemical analysiscoulometric titration coumarins count counter tube counter-current flow counter-ions in colloid chemistrycounting efficiency counting loss counting rate coupled (indicator) reaction in analysiscoupled cluster (CC) method coupled simultaneous techniques in analysiscoupling coupling constant (spin-spin) \(J\)covalent bond covalent network Cox–Yates equation cracking crazing cream cream volume creaming creep cresols critical embryo critical energy critical excitation energy \(E_{\text{q}}\) in in situ microanalysiscritical ion-concentration in an ionomer critical micelle concentration critical point critical pressure \(p_{\text{c}}\)critical quenching radius \(r_{0}\)critical solution composition critical solution point critical solution temperature critical study critical temperature \(T_{\text{c}}\)critical thickness of a film of a filmcross reaction cross-conjugation cross-flow filtration in biotechnologycross-over concentration \(c^{*}\)crossed electric and magnetic fields in mass spectrometrycrossed molecular beams crossing over in biotechnologycrosslink crosslink density crosslinking crosslinking site crowding in solvent extractioncrown crown conformation crud in solvent extractioncryogenic cryogenic sampling cryptand cryptate crystal diffraction spectrometer crystal field crystal field splitting crystal laser crystal photochemistry crystalline electrodes crystalline polymer crystallinity crystallization CT cumulative double bonds cumulative fission yield cumulative sample cumulenes cumulonimbus cloud in atmospheric chemistrycumulus cloud in atmospheric chemistrycupola curie curing current density current density (relative local) current distribution current efficiency current migration current yield Curtin–Hammett principle curve-crossing model cut off in aerosol sizes","in atmospheric chemistrycut-off filter cut-on filter CVD diamond CW cyanates cyanides cyanine dyes cyanogenic cyanohydrins cybotactic region cycles per second cyclic acid anhydrides cyclitols cyclization cyclo- cycloaddition cycloalkanes cycloalkyl groups cyclodepsipeptides cyclodextrins cycloelimination cyclohexadienyl cations cyclone (collector) in atmospheric chemistrycyclophanes cyclopolymerization cycloreversion cyclosilazanes cyclosiloxanes cyclotron cytochrome P450 cytochromes σ-constant χ-parameter
three-dimensional quantitative structure–activity relationships d, l, dl d, l, dl dalton dark current dark output dark photochemistry (photochemistry without light) dark reaction dark resistance Darlington phototransistor DAS data reduction dative bond Dauben–Salem–Turro rules daughter ion in mass spectrometrydaughter product in radiochemistryDavydov splitting day de Mayo reaction de-electronation de-energization efficiency deactivation dead time correction in radioanalytical chemistrydead time in radioanalytical chemistrydead time of an analyserdead-volume in chromatographydebye Debye–Hückel equation deca decadic absorbance \(A\)decay chain decay constant decay curve decay rate in atmospheric chemistrydecay rate of a radioactive materialdecay scheme in radioanalytical chemistrydecay time in heterogenous catalysisdeci decibel decomposition decontamination factor in liquid-liquid distributionDEDMR definitive method deflection (for a precision balance) deflocculation degeneracy degenerate chain branching degenerate chemical reaction degenerate orbitals degenerate rearrangement degree Celsius degree Fahrenheit degree of activation degree of arcdegree of association of a micelledegree of crystallinity of a polymerdegree of dissociation degree of inhibition degree of ionization degree of polymerization degree of reaction \(\alpha\)degrees of cistacticity and transtacticity degrees of freedom \(\nu\)degrees of triad isotacticity, syndiotacticity, and heterotacticity dehydroarenes dehydrobenzenes delayed coincidence delayed coke delayed coking process delayed fluorescence delayed luminescence delayed neutrons deliquescence delocalization delocalization energy delocalization in theoretical organic chemistrydemister denaturation of a macromoleculedenaturation of alcoholdendrite denitrification densification density inversion in solvent extractiondensity of states \(N_{E}\),\(r(E)\)density \(\rho\)denticity denuder system (tube or assembly) deodorizer in atmospheric chemistrydeoxyribonucleic acids depolarization of scattered light depolarizer depolymerization deposition in atmospheric chemistrydeposition velocity in atmospheric chemistrydepsides depsipeptides depth of penetration of lightdepth profile depth resolution deracemization derivative potentiometric titration derivative spectroscopy derived coherent unit derived kind of quantity derived non-coherent unit derived quantity derived unit of measurementdescending elution/development in planar chromatographydeshielding desiccant desolvation in flame spectroscopydesorption desorption (by displacement) desulfurization desymmetrization desymmetrization step detachment detailed balancing (principle of) detection efficiency in nuclear analytical chemistrydetection limit detection limit in analysisdetergent detoxification deuteriation deuteride deuterio deuterium deuteron deviation \(d\)devolatilizer dew point hygrometer (cooled surface condensation) dew point in atmospheric chemistryDexter excitation transfer dextrans dextrins DFDMR di-π-methane rearrangement di-π-silane rearrangement diabatic coupling diabatic electron transfer diabatic photoreaction diacylamines diads in polymersdiagram level in X-ray spectroscopydiagram line in X-ray spectroscopydialysate dialysis dialysis residue diamagnetic diamidides diamond diamond by CVD diamond-like carbon films dianions diastereoisomer excess diastereoisomeric units in a polymerdiastereoisomerism diastereoisomerization diastereoisomers diastereomeric ratio diastereomers diastereomorphism diastereoselectivity diastereotopic diazanylidenes diazenyl radicals diazo compounds diazoamino compounds diazoates diazonium salts diazooxides diazotates dicarbenium ions dichotomous sampler dichroic filter dichroic mirror dichroism dielectric constant dielectric polarization \(P\)dienes dienophile difference absorption spectroscopy differential capacitance differential detector in chromatographydifferential diffusion coefficient differential molar energy of adsorption differential molar interfacial energy differential molar surface excess energy differential scanning calorimetry differential thermal analysis differential viscosity diffraction diffraction analysis diffuse layer in electrochemistrydiffused junction semiconductor detector diffuser diffusion diffusion battery diffusion coefficient \(D\)diffusion control diffusion current diffusion current constant in polarographydiffusion layer diffusion layer thickness diffusion potential diffusion-controlled rate diffusional transition diffusionless transition dihedral angle diisotactic polymer dilatancy dilational transition dilational viscosity diluent gas diluent in solvent extractiondilute phase in polymer chemistrydilute solution diluter dilution rate \(D\) in biotechnologydimension of a quantitydimensionless quantities dimeric ion in mass spectrometrydimerization Dimroth–Reichardt ET parameter diode laser diols diosphenols dioxin dipolar aprotic solvent dipolar bond dipolar compounds dipolar cycloaddition dipolar ions dipolar mechanism of energy transferdipole length dipole moment dipole moment per volume dipole-induced dipole forces dipole–dipole interaction dipyrrins dipyrromethenes diradicaloid diradicals direct (radiochemical) isotope dilution analysis direct amplification direct current direct effect direct fission yield direct reaction direct thermometric method in enthalpimetric analysisdirect transfer gas flow system in spectrochemical analysisdirect-injection burner (for analytical flame spectroscopy) direct-injection enthalpimetry disaccharides discomfort threshold in atmospheric chemistrydiscontinuous analyser discontinuous indication of an analyserdiscontinuous measuring cell discontinuous phase transition discontinuous precipitation discontinuous simultaneous techniques in analysisdiscrete transport discriminant analysis discriminator disintegration constant disintegration energy \(Q\)disintegration rate of a radioactive materialdisjoining pressure (for the attraction between two surfaces) dismutation dispenser dispersion (for spectroscopic instruments) dispersion forces dispersion in atmospheric chemistrydisplacement chromatography displacive transition disproportionation disrotatory disruptor dissociation dissociation energy \(E_{\text{d}}\),\(D\)dissociative adsorption dissociative ionization in mass spectrometrydissociative surface reaction dissolution dissymmetry in stereochemistrydissymmetry of scattering distonic radical cation distribuend distribution distribution coefficient distribution constant distribution constant in chromatographydistribution function in polymersdistribution isotherm in chromatographydistribution ratio \(D\) in liquid-liquid distributiondisyndiotactic polymer ditactic polymer diterpenoids dithioacetals diurnal variation in atmospheric chemistrydividing surface DM-interference DNA DNA probe Dobson unit in atmospheric chemistrydocking studies dodecahedro- dolichols Donnan emf Donnan equilibrium Donnan exclusion Donnan pressure donor number (DN) dopant doping in catalysisdoping in polymer chemistryDoppler broadening of a spectral lineDorn effect dosage in atmospheric chemistrydose dose equivalent \(H\)dose in radioanalytical chemistrydose of a substancedose-response and dose-effect relationships double escape peak double-beam spectrometer (for luminescence spectroscopy) double-focusing mass spectrograph double-focusing mass spectrometer double-layer double-layer current double-strand chain in polymersdouble-strand copolymer double-strand macromolecule double-strand polymer double-wavelength spectroscopy doublet state doubling time \(t_{\text{D}}\) in biotechnologydown-time in analysisdownconversion downfield downstream in membrane processesdownwash in atmospheric chemistrydrift driving force (affinity) of a reaction \(A\)driving force (for electron transfer) drop time in polarographydroplet in atmospheric chemistryDrude–Nernst equation (for electrostriction) drug drug design dry bulb temperature in atmospheric chemistrydrying agent drying control chemical additive dual fluorescence of systems or molecular speciesdual substituent-parameter equation dual-mode photochromism dust collector in atmospheric chemistrydust fall in atmospheric chemistrydust in atmospheric chemistrydye laser dynamic field(s) mass spectrometer dynamic interfacial tension dynamic membrane formation dynamic quenching dynamic range of an analyserdynamic reaction path dynamic surface tension dynamic thermomechanometry dynamic viscosity \(\eta\)dyne dyotropic rearrangement dypnones Δ (delta), Λ (lambda)
E, Z E/Z photoisomerization early-downhill surface eclipsed (eclipsing) eclipsing conformation eclipsing strain ectohormone eddy eddy dispersion educt effective cadmium cut-off energy in nuclear analytical chemistryeffective charge effective chimney height effective half life effective molarity effective theoretical plate number of a chromatographic columneffective thermal cross-section effective thickness of diffusion layer effectively infinite thickness in flame spectroscopyeffectiveness effector efficiency of a counterefficiency of atomization in analytical flame spectroscopyefficiency of nebulization \(\varepsilon_{\text{n}}\) in flame spectrometryefficiency spectrum efficiency \(\eta\) of a stepefflorescence effluent effluent in chromatographyeicosanoids eighteen-electron rule einstein Einstein equation El-Sayed rules elastic collision elastic scattering in reaction dynamicselastic scattering in spectrochemistryelastically active network chain elastomer electric capacitance electric charge \(Q\)electric coherence length \(\xi_{\text{E}}\) in thin filmselectric conductance \(G\)electric conductivity electric current density \(j\)electric current \(I\)electric dipole moment \(p\)electric displacement \(D\)electric field (strength) \(E\)electric mobility \(u\),\(\mu \)electric polarizability \(\alpha\)electric potential difference \(\Delta V\) of a galvanic cellelectric potential \(V\)electric resistance \(R\)electric resistivity electric sector in mass spectrometryelectrical arc electrical double-layer electrical hygrometer electrically conducting polymer electrified interphase electro-dialysis electro-endosmosis electro-osmosis electro-osmotic hold-up time \(t_{\text{eo}}\) in capillary electromigrationelectro-osmotic mobility \(u\),\(\mu _{\text{eo}}\) in capillary electromigrationelectro-osmotic pressure electro-osmotic velocity electro-osmotic volume flow electroactive substance electrocapillarity electrocapillary equation electrochemical detector in gas chromatographyelectrochemical method of detection in analysiselectrochemical potential electrochemiluminescence electrochromic effect electrocyclic reaction electrode current density \(j\)electrode memory electrode potential \(E\)electrode process electrode reaction electrode reaction rate constants electrodecantation (or electrophoresis convection) electrodeposition electrofuge electrogenerated chemiluminescence electrographite electrokinetic potential \(\zeta\)electroluminescence electroluminescent polymer electrolytic hygrometer electromeric effect electromigration electromotive force \(E\)electron electron acceptor electron affinity \(E_{\text{ea}}\)electron attachment electron back-transfer electron beam curing electron capture electron capture detector in gas chromatographyelectron charge electron configuration electron correlation electron density electron density function electron detachment electron donor electron energy in mass spectrometryelectron exchange excitation transfer electron impact ionization in mass spectrometryelectron ionization in mass spectrometryelectron jump electron kinetic energy electron microscopy electron paramagnetic resonance electron probe microanalysis electron probe X-ray microanalysis electron rest mass electron spectroscopy for chemical analysis electron stopping power in X-ray emission spectroscopyelectron transfer electron transfer photosensitization electron work function \(\mathit{\Phi}\)electron-counting rules electron-deficient bond electron-deficient compounds electron-donor-acceptor complex electron-pair acceptor electron-pair donor electron-transfer catalysis electronation electronegativity electroneutrality principle electronic chemical potential electronic configuration electronic effect of substituents: symbols and signs electronic energy migration (or hopping) electronic stability electronic state electronically excited state electronvolt electrophile electrophilicity electrophoresis electrophoresis convection electrophoretic mobility \(\mu\)electrophoretic velocity \(\nu_{\text{ep}}\)electrophotography electrosmosis electrostatic filter electrostatic precipitator electrostriction electrothermal atomizer in spectrochemical analysiselectroviscous effects element element effect element of chirality elementary charge \(e\)elementary entity elementary particle in nuclear chemistryelementary reaction elimination eluate eluent elute elution elution band in chromatographyelution chromatography elution curve elutriation emanation thermal analysis embryo emission emission anisotropy emission control equipment in atmospheric chemistryemission flux in atmospheric chemistryemission in atmospheric chemistryemission spectrum emittance \(\varepsilon\)empirical formula emulsifier emulsion enamines enantioconvergence enantioenriched enantiomer enantiomer excess enantiomeric groups enantiomeric purity enantiomeric ratio enantiomeric units in a polymerenantiomerically enriched enantiomerically pure enantiomerism enantiomerization enantiomorph enantiomorphous structures in polymersenantiopure enantioselectivity enantiotopic enantiotropic mesophase enantiotropic transition encapsulation in catalysisencounter encounter complex encounter control encounter pair encounter-controlled rate end-group end-point end-to-end distance in polymersend-to-end vector in polymersendergonic reaction endo, exo, syn, anti endocytosis endoenzymes endothermic reaction ene reaction energized species energy dispersion in emission spectrometryenergy dispersive detector energy dispersive X-ray fluorescence analysis energy flux density energy gradient energy hypersurface energy migration energy of a radiationenergy of activation energy of activation of an electrode reactionenergy pooling energy profile energy resolution in radiochemistryenergy storage efficiency \(\eta\)energy threshold in radiochemistryenergy transfer in photochemistryenergy transfer plot in photochemistryenergy yield of luminescence energy \(E\)enforced concerted mechanism enhanced phosphorescence analysis in luminescence spectroscopyenhancement reaction in analytical chemistryenhancer enolates enols enophile enoses enrichment factor \(S\) in liquid-liquid distributionenrichment, isotopic ent entanglement network entatic state entering group enthalpimetric analysis enthalpimetric flow injection analysis enthalpimetric titration enthalpimetry enthalpogram enthalpy of activation \(\Delta ^{\ddagger}H^{\,\unicode{x26ac}}\)enthalpy of immersion enthalpy of wetting enthalpy \(H\)entitic entitic quantity entrainment in atmospheric chemistryentrainment in photochemistryentrance channel entropy of activation \(\Delta ^{\ddagger}S^{\,\unicode{x26ac}}\)entropy unit entropy \(S\)envelope conformation environmental monitoring environmental stress cracking enzyme activator enzyme activity enzyme induction in general chemistryenzyme induction in medicinal chemistryenzyme inhibitor enzyme repression enzyme substrate electrode enzyme thermistor enzymes enzymic decomposition epi-phase epicadmium neutrons epigenetic epihalohydrins epimerization epimers episulfonium ions epithermal neutrons epitope epoxides epoxy compounds equalization of electronegativity, principle of equatorial equilibration equilibrium constant equilibrium control equilibrium dialysate equilibrium distance in a moleculeequilibrium film equilibrium geometry equilibrium isotope effect equilibrium reaction equilibrium sedimentation equilibrium solution equivalence point equivalence postulate in polymer chemistryequivalent chain in polymersequivalent diameter equivalent entity erg error of measurementerythro structures in a polymererythro, threo ESCA escape depth (for surface analysis techniques) Esin and Markov coefficient esters ET-value \(E_{\text{T}}\)ethers euatmotic reaction eupeptide bond eutectic reaction evaluation function evaporation even-electron ion evolved gas analysis evolved gas detection Ewens–Bassett number exa excess acidity excess mass (at a solid/liquid interface) excess Rayleigh ratio excess volume (at a solid/liquid interface) exchange current of an electrode reactionexchange extraction exchange integral exchange labelling exchange repulsion exchange-inversion transition excimer excimer lamp excimer laser excimer-luminescence in luminescence quenchingexcipient in toxicologyexciplex exciplex-luminescence in luminescence quenchingexcitation excitation energy excitation energy in in situ microanalysisexcitation level in X-ray spectroscopyexcitation spectrum excitation transfer excitation-emission spectrum excited state exciton excluded volume of a macromolecule in polymersexcluded volume of a segment in polymersexclusion chromatography exergonic reaction exfoliated graphite exfoliation exit channel exitance exo exoenzymes exon exothermic reaction expansion factor in polymersexpectation value expected value experimental perturbational calculation explosivity limits exponential decay exposure in medicinal chemistryexposure in nuclear chemistryexposure in photochemistryexpression in biotechnologyextended Hammett equation extended Hückel MO method extended X-ray absorption fine structure extended-chain crystal in polymersextender extensive quantity extent of an interface (surface) extent of reaction \(\xi\)external compensation external heavy atom effect external ion return external ion-pair return external photoelectric effect external return external standard in chromatographyexternal surface exterplex extinction extinction coefficient extra-column volume in chromatographyextract (noun) extract (verb) extractability in solvent extractionextractant extracting agent extraction extraction (equilibrium) constant extraction coefficient extraction factor \(D_{\text{m}}\)extraction fractionation of polymersextraction in process liquid-liquid distributionextraction isotherm extraction process in catalysisextrapolated range in radiochemistryextremophiles extrusion transformation α-expulsion in photochemistryπ-electron acceptor/donor group ρσ-equation
f number f-functional branch point f-functional branch unit fabric filter fac- factor factor-group splitting fall time fallout in atmospheric chemistryfanning in atmospheric chemistryfarad faradaic current faradaic current density faradaic demodulation current faradaic rectification current Faraday constant Faraday cup collector fast atom bombardment ionization fast neutrons fast-atom bombardment (FAB) mass spectroscopy fatigue of a photochromic systemfatty acids feed rate in catalysisfeed-back inhibition in biotechnologyfeedback in analysisfeedback in kineticsfemto fenestranes Fenton reaction fermentation fermenter fermi Fermi energy Fermi level \(E_{\text{F}}\)fermion feromone ferredoxin ferrimagnetic transition ferrocenophanes ferroelastic transition ferroelectric (antiferroelectric) transition ferroelectric polymer ferroic transition ferromagnetic polymer ferromagnetic transition fertile in radioanalytical chemistryfibrillar morphology fibrous activated carbon fibrous carbon fibrous crystal in polymers in polymersfiducial group field desorption in mass spectrometryfield effect field effect phototransistor field ionization in mass spectrometryfield level filamentous carbon filler filler coke filling solution of a reference electrodefilm film badge in radioanalytical chemistryfilm element film tension filter filter of a radiationfilter spectrometer filtration fine structure constant \(\alpha\)first-order phase transition first-pass effect Fischer projection Fischer–Rosanoff convention Fischer–Tollens projection fissile of a materialfission fragment ionization in mass spectrometryfission fragments fission neutrons fission products fission yield fissionable fixed ions fixed neutral loss (gain) scan in mass spectrometryfixed neutral loss (gain) spectrum in mass spectrometryfixed precursor ion scan in mass spectrometryfixed product ion scan in mass spectrometryfixed product ion spectrum in mass spectrometryflagpole flame ionization detector in gas chromatographyflame photometric detector in gas chromatographyflame photometry flame-in-tube atomizer in spectrochemical analysisflammable limits flash fluorimetry flash lamps flash photolysis flash point flash vacuum pyrolysis flat band potential (at a semiconductor/solution interphase) flat bands flavins flavonoids (isoflavonoids and neoflavonoids) flavoproteins flavylium salts floating monolayer floc flocculation floccule Flory–Huggins theory flotation flow analysis flow birefringence flow enthalpimetry flow injection flow injection enthalpimetry flow rate in chromatographyflow rate in flame emission and absorption spectrometryflow rate of a quantityflow rate of unburnt gas mixture in flame emission and absorption spectrometryflow reactor flow resistance parameter \(\mathit{\Phi}\) in chromatographyflow-programmed chromatography flue gas in atmospheric chemistryflue gas scrubber in atmospheric chemistryfluence rate \(E_{\unicode{x26ac}}\)fluence \(F\),\(\varPsi \),\(H_{0}\)fluid coke fluidity \(\phi\)fluidized bed fluoresceins fluorescence fluorescence error in spectrochemical analysisfluorescence excitation of X-raysfluorescence lifetime fluorescence resonance energy transfer fluorescence yield fluorimeter fluorocarbons fluorogenic fluorohydrins fluorophore flux depression flux \(J_{\text{X}}\) of a quantityfluxional fly ash in atmospheric chemistryfoam foam fractionation foaming agent fog fog horizon in atmospheric chemistryfolates fold domain in polymer crystalsfold in polymer crystalsfold plane in polymer crystalsfold surface in polymer crystalsfolded-chain crystal in polymersfoot forbidden line in X-ray spectroscopyforce constants force-field calculation force \(F\)foreign-gas broadening formamidine disulfides formation constant formazans Förster cycle Förster excitation transfer Förster-resonance-energy transfer forward scattering fossil fuel fouling agent in catalysisfouling in membrane processesFourier transform ion cyclotron resonance (FT-ICR) mass spectrometer Fourier transform spectrometer Fourier-transform spectroscopy fractal agglomerate fractal dimension \(d\)fraction fraction collector in chromatographyfraction extracted \(E\)fractional change of a quantity fractional selectivity in catalysisfractionation of analytesfractionation of polymersfragment ion in mass spectrometryfragmentation fragmentation reaction in mass spectrometryframe-shift mutation Franck–Condon principle Franck–Condon state franklin free charge density on the interface free electron laser free energy free radical free rotation free spiro union free-running laser freely draining freely jointed chain in polymersfreely rotating chain in polymersfreezing freezing out in atmospheric chemistryfrequency distribution frequency doubling frequency-domain fluorometry frequency \(f\),\(\nu \)frequency \(\nu\),\(\omega\) in photochemistryFRET friction coefficient friction factor \(\mu\)frictional coefficient \(f\) in polymer chemistryfringed-micelle model in polymer crystalsfront surface geometry in luminescencefrontal chromatography frontier orbitals fronting in chromatographyfrost point hygrometer froth flotation Frumkin effect fucolipid fuel cycle (nuclear) fuel element (nuclear) fuel reprocessing (nuclear) fugacity coefficient \(\phi\)fugacity \(f\),\(\tilde{p}\)fulgides full energy peak fullerenes fulminates fulvalenes fulvenes fume in atmospheric chemistryfumes fumigation in atmospheric chemistryfunctional class name functional group functional parent functional polymer functionality \(f\) of a monomerfungicide furanocoumarins furanoses furnace black furnace pyrolysis in spectrochemical analysisfurocoumarins fusion in biotechnologyfusion name FWHM (Full Width at Half Maximum)
G value in nuclear chemistrygain \(G\) of a photomultiplierGalvani potential difference galvanic corrosion gas analysis installation in atmospheric chemistrygas black gas chromatography gas constant gas laser gas sensing electrode gas-filled phototube gas-filled X-ray detector gas-liquid chromatography gas-phase acidity gas-phase basicity gas-phase-grown carbon fibres gas-solid chromatography gaseous diffusion separator in atmospheric chemistrygated photochromism gated photodetector gauche gauche conformation in polymersgauche effect gauss Gaussian band shape Geiger counter Geiger–Muller counter tube gel gel aging gel fraction gel permeation chromatography gel point gel time gelation gelation temperature geminate ion pair geminate pair geminate recombination gene gene amplification gene library gene manipulation general acid catalysis general acid–base catalysis general base catalysis general force field generalized transition-state theory generally labelled tracer generation time \(t_{\text{G}}\) in biotechnologygenetic algorithm genetic code genome genomics genotype geometric mean \(\bar{x}_{g}\)geometric attenuation geometric isomerism geometric surface (interface) area geometrical equivalence in polymersgeometry (counting) in radioanalytical chemistrygeometry factor in radioanalytical chemistrygermylenes germylidenes Gibbs adsorption Gibbs dividing surface Gibbs energy (function) \(G\)Gibbs energy diagram Gibbs energy of activation \(\Delta ^{\ddagger}G^{\,\unicode{x26ac}}\)Gibbs energy of photoinduced electron transfer Gibbs energy of repulsion Gibbs energy profile Gibbs film elasticity Gibbs surface giga glass electrode error glass laser glass transition glass-like carbon glass-transition temperature global analysis globular-chain crystal in polymersglove box glycals glycans glycaric acids glycerides glycerophospholipid glycitols glyco-amino-acid glycoconjugate glycoglycerolipid glycolipids glycols glyconic acids glycopeptides glycoproteins glycosamines glycosaminoglycan glycoses glycosides glycosphingolipid glycosyl group glycosyl-amino-acid glycosylamines glycuronic acids Gouy layer in electrochemistrygrab sampling gradient gradient elution in chromatographygradient layer in chromatographygradient packing gradientless reactor in catalysisgradual (sudden) potential-energy surface graft copolymer graft copolymerization graft macromolecule graft polymer grafting in catalysisgrafting in polymer chemistrygram Gram stain granular carbon graphene layer graphite graphite electrode graphite fibres graphite material graphite whiskers graphitic carbon graphitizable carbon graphitization graphitization heat treatment graphitized carbon gravimetric method gravitational constant gray green body green coke greenhouse effect in atmospheric chemistryGrignard reagents grist grit in atmospheric chemistryground level concentration in atmospheric chemistryground level inversion in atmospheric chemistryground state group group electronegativity group preconcentration in trace analysisgrowth curve of activitygrowth rate in biotechnologyGrunwald–Winstein equation guest Guinier plot gustiness in atmospheric chemistryhybrid material γ-cascade
Haber–Weiss reaction haem halato-telechelic polymer halatopolymer half life of a radionuclidehalf life \(t_{1/2}\)half thickness in radiochemistryhalf-chair half-life \(T_{1/2}\) of a photochromic systemhalf-life \(\tau_{1/2}\) of a transient entityhalf-peak potential half-wave potential half-width of a bandhalirenium ions halochromism haloforms halohydrins halonium ions halophiles hamiltonian operator \(\hat{H}\)Hammett acidity function Hammett equation Hammond principle Hammond–Herkstroeter plot handedness Hansch analysis Hansch constant Hantzsch–Widman name hapten hapto hard acid hard amorphous carbon films hard base hard-segment phase domain hard-sphere collision cross section harmonic approximation harmonic frequency generation harmonic mean harpoon mechanism hartree Hartree energy Haworth representation hazard haze horizon in atmospheric chemistryhaze in atmospheric chemistryhealth surveillance heat capacity of activation \(\Delta ^{\ddagger}C_{p}^{\,\unicode{x26ac}}\)heat capacity \(C\)heat flux \(J_{q}\)heat \(q\),\(Q\)heavy atom effect heavy atom isotope effect heavy water hecto height equivalent to a theoretical plate (h.e.t.p.) in chromatographyheight equivalent to an effective theoretical plate in chromatographyhelicenes helicity heliochromism helion helium dead-space in colloid and surface chemistryhelium ionization detector in gas chromatographyhelium–cadmium laser helium–neon laser helix helix residue in a polymerhelix sense Helmholtz energy (function) \(A\)hemes (heme derivatives) hemiacetals hemiaminals hemiketals hemileptic hemins hemochromes hemodialysis hemoglobins Henderson–Hasselbalch equation henry Henry's law Herkstroeter plot hertz Herz compounds hetarenes hetaryl groups hetarynes heteroalkenes heteroarenes heteroaryl groups heteroarynes heterobimetallic complex heterochain polymer heteroconjugation heterocumulenes heterocyclic compounds heterocyclyl groups heterodetic cyclic peptide heterodisperse heteroexcimer heterogeneity in analytical chemistryheterogeneous catalysis heterogeneous diffusion rate constant in electrochemistryheterogeneous membrane electrode heterogeneous nucleation heteroleptic heterolysis heterolytic bond-dissociation energy heterolytic dissociative adsorption heteropolysaccharide heterotactic polymer heterotactic triads in polymersheterotopic heterotrophic (organisms) heterovalent hyperconjugation hexagonal graphite hexahedro- in inorganic nomenclaturehexaprismo- in inorganic nomenclaturehidden return high resolution energy loss spectroscopy high-pressure graphitization high-pressure mercury lamp (arc) high-spin higher-order transition highly oriented pyrolytic graphite Hildebrand parameter hindered rotation hipping histones Hofmann rule hold-back carrier hold-up volume \(V_{\text{M}}\),\(t_{\text{M}}\) in column chromatographyhold-up volume in chromatographyhole burning hole transfer holoenzyme Holtsmark broadening of a spectral linehomo homoaromatic homochain polymer homochiral homoconjugation homocyclic compounds homodesmotic reaction homodetic cyclic peptide homogeneity in analytical chemistryhomogeneous catalysis homogeneous membrane electrode homogeneous nucleation homogeneous nucleus homogeneous polymer blend homoleptic homologous polymer blend homolysis homolytic dissociative adsorption homomorphic homopolymer homopolymerization homopolysaccharide homotopic horizontal elution in planar chromatographyhost in biotechnologyhost-vector system hot atom hot cell hot ground state reaction hot quartz lamp hot state reaction hour Hückel (4n + 2) rule Hückel molecular orbital (HMO) theory Huggins coefficient \(k_{\text{H}}\)Huggins equation hula-twist (HT) mechanism humidity in atmospheric chemistryHund rules Hush model HWHM (Half Width at Half Maximum) hybrid orbital hybrid polymer hybridization hybridoma hydration hydrazide hydrazones hydrazide imides hydrazides hydrazidines hydrazines hydrazinylidenes hydrazo compounds hydrazones hydrazonic acids hydride hydro hydrocarbon cracking hydrocarbons hydrocarbyl groups hydrocarbylene groups hydrocarbylidene groups hydrocarbylidyne groups hydrocarbylsulfanyl nitrenes hydrocracking unit hydrodynamic volume in polymershydrodynamically equivalent sphere in polymershydrogel hydrogen hydrogen bond hydrogen bond in theoretical organic chemistryhydrogen gas electrode hydrolases hydrolysis hydrolysis ratio \(r_{\text{w}}\)hydrometeor in atmospheric chemistryhydron hydroperoxides hydrophilic hydrophilicity hydrophobic interaction hydrophobicity hydropolysulfides hydrosphere in atmospheric chemistryhydrosulfides hydroxamic acids hydroximic acids hydroxylamines hygrometer hygrometry (moisture analysis) hyperchromic effect hyperconjugation hypercoordination hyperfine (interaction) hyperfine coupling hyperpolarizability (of nth order) hypersatellite in X-ray spectroscopyhypervalency hypho- hypo-phase hypochromic effect hypsochromic shift hysteresis η (eta or hapto) in inorganic nomenclature
(chain) identity period of a polymer of a polymerIC icosahedro- icosanoids ICT ICT emission ideal adsorbed state ideal chromatography ideal dilute solution ideal gas ideal mixture ideal, non-linear chromatography ideally polarized (electrified) interphase ideally unpolarized (electrified) interphase identity reaction illuminance \(E\),\(E_{\text{v}}\)image converter tube image dissection tube imaging (photoimaging) imbalance imbibition in colloid chemistryimenes imides imidic acids imidines imidogens imidonium ions imidoyl carbenes imidoyl nitrenes imin imine radical imines iminium compounds imino acids imino carbenes iminooxy radicals iminoxyl radicals iminyl carbenes iminyl radicals iminylium ions immersional wetting immiscibility immiscible polymer blend immission dose in atmospheric chemistryimmission flux in atmospheric chemistryimmission in atmospheric chemistryimmission rate in atmospheric chemistryimmobile adsorption immobilization by adsorption immobilization by inclusion immobilization in biotechnologyimmobilized enzyme immobilized phase in chromatographyimmune response immunization immunoassay immunochemistry immunogen immunoglobulin immunoradiometric assay immunosuppression impact parameter \(b\)impact-modified polymer impaction impedance \(Z\)impingement impinger imprecision in analysisimpregnation in chromatographyimpregnation in polymer chemistryimproved canonical variational transition-state theory impulsive reaction in situ micro-X-ray diffraction in situ microanalysis in vitro in vivo in-laboratory processing in analytical chemistryin-out isomerism in situ composite formation inaccuracy in analysisinch incidence in medicinal chemistryincinerator inclusion compound incoherent radiation incoherent scattering incoherent structure incongruent reaction increment (for bulk materials and large units) indicated hydrogen indicator (visual) indicator electrode indicator reaction indifferent absorbing ion indifferent electrolyte indirect amplification indirect reaction individual gauge for localized orbitals individual isotherm individual particle analysis individual perception threshold in atmospheric chemistryinduced radioactivity induced reaction inducer in enzyme catalysisinduction induction period inductive effect inductomeric effect inductor inelastic collision inelastic scattering inert inert gas inertial defect inertial separator infinite source thickness information theory infrared inherent viscosity of a polymerinhibition inhibitor inhibitory concentration \(\text{IC}\)inhibitory dose \(\text{ID}\)inhomogeneity error in spectrochemical analysisinitial (final) state correlations initial energy initial rate method initiation initiator injection temperature in chromatographyinner electric potential \(\phi\)inner filter effect inner Helmholtz plane inner layer in electrochemistryinner orbital X-ray emission spectra inner salts inner-sphere electron transfer inoculation inorganic polymer inorganic–organic polymer inositols input rate in analysisinsert in biotechnologyinsertion instability (with reference to instrumentation) instability of Hartree–Fock solution instantaneous sampling in atmospheric chemistryinstantaneous current instantaneous rate of flow in polarographyinstrumental activation analysis instrumental dependability instrumental indication (for a precision balance) integral capacitance of an electrodeintegral detector in chromatographyintegrating sphere intended crossing of potential-energy surfacesintensity intensity (relative to base peak) in mass spectrometryintensive quantity interaction distance intercalation compounds intercalation in polymer chemistryintercalation reaction interchange reaction interchromophoric radiationless transition interconal region interconvertible enzyme interface interfacial adhesion interfacial concentration \(c\) in electrochemistryinterfacial double-layer interfacial layer interfacial layer width \(\sigma_{\text{S}}\) in thin filmsinterfacial region interfacial tension interference filter interference in analysisinterfering lines interfering substance in electroanalytical chemistryinterferometer interferons intermediate intermediate neutrons intermolecular intermolecular radiationless transition internal absorptance \(\alpha_{\text{i}}\)internal compensation internal conversion internal energy \(U\)internal filling solution of a glass electrodeinternal reference electrode internal return internal standard in chromatographyinternal surface internal transmittance internal valence force field international calorie International system of units international unit interparticle porosity \(\varepsilon\) in chromatographyinterparticle volume of the column \(V_{0}\) in chromatographyinterpenetrating polymer network interphase interphase transition intersection space interstitial fraction in chromatographyinterstitial velocity in chromatographyinterstitial volume in gas chromatographyintersystem crossing interval analysis intervalence charge transfer interzonal region intimate ion pair intra- in organic reaction mechanismsintrachromophoric radiationless transition intramolecular intramolecular catalysis intramolecular charge transfer intramolecular isotope effect intraphase transition intrinsic activation energy \(E_{\text{a,i}}\)intrinsic barrier intrinsic detector efficiency intrinsic full energy peak efficiency intrinsic photopeak efficiency intrinsic reaction coordinate intrinsic viscosity of a polymerintrinsically conducting polymer intron inverse isotope effect inverse kinetic isotope effect inverse micelle inverse square law in radiation chemistryinversion inversion height in atmospheric chemistryinversion point in phase transitionsinverted micelle inverted region (for electron transfer) iodohydrins iodometric titration iodonium ions ion ion collector in mass spectrometryion cyclotron resonance (ICR) mass spectrometer ion energy loss spectra in mass spectrometryion exchange ion exchanger ion kinetic energy spectrum in mass spectrometryion laser ion microscopy ion pair ion pair return ion probe microanalysis ion pumps ion radical ion scattering spectrometry ion source in mass spectrometryion trap mass spectrometer ion-containing polymer ion-exchange chromatography ion-exchange isotherm ion-exchange membrane ion-exchange polymer ion-free layer ion-pair formation in mass spectrometryion-selective electrode ion-selective electrode cell ion/molecule reaction in mass spectrometryion/neutral species exchange reaction in mass spectrometryion/neutral species reaction in mass spectrometryionene ionic aggregates in an ionomer ionic bond ionic concentration ionic conductivity ionic copolymerization ionic dissociation in mass spectrometryionic polymer ionic polymerization ionic spectral lines ionic strength \(I\)ionic transport number \(t\)ionization ionization buffer in flame spectroscopyionization by sputtering ionization chamber ionization cross-section ionization efficiency ionization efficiency curve in mass spectrometryionization energy \(E_{\text{i}}\)ionization potential ionizing collision in mass spectrometryionizing power ionizing radiation ionizing voltage ionogenic groups ionomer ionomer cluster ionomer molecule ionomer multiplet ionophore ipso-attack iridescent layers iridoids iron-sulfur cluster iron-sulfur proteins irradiance (at a point of a surface) \(E\)irradiation irregular macromolecule irregular polymer irreversible transition ISC isoabsorption point isobar in atmospheric chemistryisobaric mass-change determination isobaric separation isobars isoclined structures in polymersisoclinic point isoconfertic separation isoconjugate systems isocoumarins isocratic analysis in chromatographyisocyanates isocyanides isocyclic compounds isodesmic reaction isodiazenes isoelectric isoelectric point in electrophoresisisoelectronic isoemissive point isoentropic isoenzyme isoequilibrium relationship isoflavonoids isogyric reaction isoionic isoionic point in electrophoresisisokinetic line in atmospheric chemistryisokinetic relationship isokinetic sampling in atmospheric chemistryisolampsic point isolated double bonds isolobal isomer isomer shift in Mössbauer spectroscopyisomerases isomeric isomeric state in nuclear chemistryisomeric transition in nuclear chemistryisomerism isomerization isometric isomorphic polymer blend isomorphous structures in polymersisonitriles isonitroso compounds isooptoacoustic point isopeptide bond isopotential point isoprenes isoprenoids isopycnic isopycnic separation isorefractive isosbestic point isoselective relationship isoselenocyanates isostatic pressing isosteric enthalpy of adsorption isostilbic point isostructural reaction isotactic macromolecule isotactic polymer isotactic triads in polymersisotherm in atmospheric chemistryisothermal chromatography isothiocyanates isotones isotope dilution isotope dilution analysis isotope effect isotope exchange isotope exchange analysis isotope pattern in mass spectrometryisotopes isotopic abundance isotopic carrier isotopic enrichment isotopic enrichment factor isotopic fractionation factor isotopic ion isotopic labelling isotopic molecular ion isotopic scrambling isotopic separation isotopic tracer isotopically deficient isotopically enriched ions isotopically labelled isotopically modified isotopically substituted isotopically unmodified isotopologue isotopomer isotropic isotropic carbon isotropic pitch-based carbon fibres isoureas isovalent hyperconjugation isozyme
j-value in atmospheric chemistryJablonski diagram Jahn–Teller effect Jahn–Teller transition joule junction point junction unit junction-point density
Kamlet–Taft solvent parameters Kaptein–Closs rules Kasha rule Kasha–Vavilov rule katal Kekulé structure (for aromatic compounds) kelvin \(\text{K}\)ketals ketazines ketenes ketenimines ketides ketimines keto keto carbenes ketoaldonic acids ketoaldoses ketones ketoses ketoximes ketyls kilo kilogram \(\text{kg}\)kind-of-property kind-of-quantity kinematic viscosity \(\nu\)kinematics kinetic activity factor kinetic ambiguity kinetic control of product compositionkinetic current kinetic electrolyte effect kinetic energy \(E_{\text{k}}\)kinetic equivalence kinetic isotope effect kinetic method of analysiskinetic resolution kinetic synergist kinetic theory of collisions klado- Koopmans' theorem Koppel–Palm solvent parameters Kosower Z-value Kováts index Krafft point Kratky plot krypton ion laser κ (kappa) in inorganic nomenclature
L l l, u label labelling labile laboratory sample lachrymator lactams lactides lactims lactols lactones ladder chain ladder macromolecule ladder polymer LADS lag phase in biotechnologylambda Lambert law lamellar crystal lamp lamp black Landau–Zener model Landolt reaction Langmuir monolayer Langmuir–Blodgett (LB) membrane Langmuir–Hinshelwood mechanism Langmuir–Rideal (Rideal–Eley) mechanism Laporte rule lapse rate in atmospheric chemistrylarge particle in radiation scatteringlariat ethers LAS laser laser beam ionization laser dye laser ionization in mass spectrometrylaser micro emission spectroscopy laser micro mass spectrometry laser Raman microanalysis laser-jet photochemical technique lasing late-downhill surface latent image latent period in medicinal chemistrylateral order in a polymerlateral resolution in in situ microanalysislatex lath crystal lattice distortion laws of distribution in precipitationlayer layer equilibrium in chromatographyleader sequence in biotechnologyleast motion, principle of least-squares technique leaving group lecithins lectins LED Leffler's assumption left-to-right convention length \(l\)lethal concentration lethal dose lethal synthesis leuco bases leuco compounds leukotrienes level level width \(\mathit{\Gamma}\)levelling effect Lewis acid Lewis acidity Lewis adduct Lewis base Lewis basicity Lewis formula (electron dot or Lewis structure) Lewis octet rule LIDAR in atmospheric chemistrylifetime of luminescencelifetime \(\tau\)ligand field ligand field splitting ligand to ligand charge transfer (LLCT) transition ligand to metal charge transfer (LMCT) transition ligands ligases ligate light polarization light scattering light source light-atom anomaly light-emitting diode lignans lignins limit of detection in analysislimit test in toxicologylimiting adsorption current limiting catalytic current limiting condition of operation limiting current limiting differential diffusion coefficient limiting diffusion current limiting kinetic current limiting mean limiting migration current limiting sedimentation coefficient limiting viscosity number line formula line repetition groups line width line width in Mössbauer spectroscopyline-of-centres model line-shape analysis linear (decadic) absorption coefficient in optical spectroscopylinear attenuation coefficient in optical spectroscopylinear absorption coefficient linear attenuation coefficient linear chain linear chromatography linear copolymer linear dichroism linear dispersion linear distribution isotherm in chromatographylinear electron accelerator linear energy transfer linear free-energy relation linear Gibbs energy relation linear macromolecule linear polarizer linear polymer linear pulse amplifier linear range linear solvation energy relationships linear strain \(\varepsilon\),\(e\)linearity of responsivity of a radiation detectorlineic Lineweaver–Burk plot linked scan in mass spectrometrylipid film lipids lipophilic lipophilicity lipophobic lipopolysaccharides lipoproteins liposome Lippman's equation liquid chromatography liquid crystal liquid excimer laser liquid ion exchange liquid ion laser liquid junction liquid laser liquid membrane liquid scintillation detector liquid volume in gas chromatographyliquid-coated stationary phase (material) in liquid chromatographyliquid-crystal dendrimer liquid-crystal polymer liquid-crystal state liquid-crystal transitions liquid-crystalline phase liquid-crystalline polymer liquid-gel chromatography liquid-liquid distribution (extraction) (partition) liquid-liquid extraction liquid-phase loading in chromatographyliquidus lithometeor in atmospheric chemistrylithosphere in atmospheric chemistrylitre live time living copolymerization living polymer living polymerization load (on a precision balance) loading capacity in solvent extractionlocal conformation of a polymerlocal current density local efficiency of atomization \(\varepsilon_{\text{a}}\) in flame spectrometrylocal flame temperature \(T_{1}\) in flame emission and absorption spectrometrylocal fraction atomized \(\chi _{\text{a}}\),\(\beta_{\text{a}}\) in flame emission and absorption spectrometrylocal fraction desolvated \(\chi _{\text{s}}\),\(\beta_{\text{s}}\) in flame emission and absorption spectrometrylocal fraction volatilized \(\chi _{\text{v}}\),\(\beta_{\text{v}}\) in flame emission and absorption spectrometrylocalized adsorption localized molecular orbitals localized-itinerant transition lock-in state log-normal distribution logarithmic distribution coefficient logarithmic normal distribution of a macromolecular assemblylogarithmic viscosity number logit London forces London–Eyring–Polanyi (LEP) method London–Eyring–Polanyi–Sato (LEPS) method lone (electron) pair long chain long spacing in polymer crystalslong-chain branch long-lived collision complex long-range intramolecular interaction in polymerslongitudinal order in a polymerloose end loose ion pair Lorentz broadening of a spectral lineLorentzian band shape Lorenz–Mie theory lot in analytical chemistrylow energy electron diffraction low pressure electrical discharge low temperature UV–VIS absorption spectroscopy low-pressure diamond low-pressure mercury lamp (arc) low-spin low-spin state lowest lethal concentration found lowest observed adverse effect level lowest-observed-adverse-effect-level lowest-observed-effect-level lumen luminance luminescence luminescence quenching luminescence spectrometer luminous flux luminous intensity \(I_{\text{v}}\)luminous quantities lumiphore LUMO lux lyases lyate ion lyonium ion lyophilic lyophilic sols lyophobic lyotropic mesophase lysimeter Λ (lambda)
E/2 mass spectrum M machine in analysismacrocycle macrolides macrometeorology in atmospheric chemistrymacromolecular macromolecular isomorphism macromolecule macromonomer macromonomer molecule macromonomer unit macromonomeric unit macropore in catalysismacroporous polymer macroradical macroscopic cross-section macroscopic diffusion control macroscopic film macroscopic kinetics magic acid magic angle magnetic circular dichroism magnetic coherence length \(\xi_{\text{M}}\)magnetic deflection in mass spectrometrymagnetic equivalence magnetic field (B) scan in mass spectrometrymagnetic field strength \(H\)magnetic flux density in Mössbauer spectroscopymagnetic flux density \(B\)magnetic flux \(\mathit{\Phi}\)magnetic induction magnetic moment \(m\),\(\mu\)magnetic resonance imaging magnetic susceptibility magnetic susceptibility \(\chi\)magnetic transition magnetizability \(\xi\)magnetization transfer magnetogyric ratio \(\gamma\)main chain (backbone) of a polymermain-chain polymer liquid crystal main-chain scission mancude-ring systems mancunide-ring systems manipulator manual in analysismapping in biotechnologyMarangoni effect Marcus equation (for electron transfer) Marcus inverted region (for electron transfer) Marcus–Coltrin path Marcus–Hush relationship Mark–Houwink equation marker Markownikoff rule martensitic transition mass (weight) of the stationary phase \(W_{\text{s}}\) in chromatographymass analysis in mass spectrometrymass balance in atmospheric chemistrymass concentration \(\gamma\),\(\rho\)mass density mass density gradient \(\bigtriangledown \rho\),\(\text{grad}\: \rho\)mass distribution ratio mass distribution ratio in chromatographymass distribution ratio \(k_{\text{MEEKC}}\) in micro-emulsion electrokinetic chromatographymass distribution ratio \(k_{\text{MEKC}}\) in micellar electrokinetic chromatographymass excess \(\mathit{\Delta}\)mass flow rate \(q_{\text{m}}\)mass fraction \(w\)mass number \(A\)mass peak in mass spectrometrymass range in mass spectrometrymass resolving power in mass spectrometrymass spectrograph mass spectrometer mass spectrometer (operating on the linear accelerator principle) mass spectrometer focusing system (deflection system) mass spectrometric detector in gas chromatographymass spectrometry mass spectroscope mass spectroscopy mass spectrum mass transfer coefficient in electrochemistrymass transfer in biotechnologymass-average velocity in electrolytesmass-distribution function mass-flow sensitive detector in chromatographymass-law effect mass-to-charge ratio \(m_{\text{z}}\) in mass spectrometrymass-transfer-controlled electrolyte rate constant mass \(m\)massic massive transition matched cells in spectrochemical analysismaterial safety data sheet matrix effect in surface analysismatrix in analysismatrix isolation Mattauch–Herzog geometry maximum allowable concentration in atmospheric chemistrymaximum emission concentration in atmospheric chemistrymaximum hardness, principle of maximum latent period maximum loading maximum permissible daily dose maximum permissible level maximum storage life maximum tolerable concentration maximum tolerable dose maximum tolerable exposure level maximum tolerated dose McLafferty rearrangement in mass spectrometrymean \(\bar{x}\)mean activity of an electrolyte in solution in mass spectrometrymean catalytic activity rate \(\frac{\Delta z}{\Delta t}\)mean current density mean exchange current density mean free path \(\lambda\)mean interstitial velocity of the carrier gas in chromatographymean life \(\tau\)mean lifetime \(\tau\)mean linear range in nuclear chemistrymean mass range in nuclear chemistrymean mass rate \(\frac{\Delta m}{\Delta t}\)mean residence time of adsorbed moleculesmean substance rate \(\frac{\Delta n}{\Delta t}\)mean volume rate \(\frac{\Delta V}{\Delta t}\)measurable quantity measurand measured excitation spectrum measured spectrum measured value in analysismeasurement measurement resolution in atmospheric trace component analysismeasurement result measurement solution in analysismeasurement threshold of an analysermechanical entrapment mechanical hygrometer mechanical inhibitor mechanism of a reactionmechanism-based inhibition mechanization in analysisMechano-chemical reaction median median effective concentration \(\text{EC}_{50}\)median effective dose \(\text{ED}_{50}\)median lethal concentration \(\text{LC}_{50}\)median lethal dose \(\text{LD}_{50}\)median lethal time \(\text{TL}_{50}\)median narcotic concentration \(\text{NC}_{50}\)median narcotic dose \(\text{ND}_{50}\)medium medium effect medium-pressure mercury lamp mega meiosis Meisenheimer adduct Meker burner melting melting point (corrected/uncorrected) membrane membrane emf membrane in an ion-selective electrodemembrane potential membrane sites in an ion-selective electrodememory effect in atmospheric chemistrymer mer- in inorganic nomenclaturemercaptals mercaptans mercaptides mercaptoles mercury flow system in spectrochemical analysismercury–xenon lamp mero merry-go-round reactor meso meso structures in polymersmeso-compound mesogen mesogenic group mesogenic monomer mesogenic pitch mesoionic compounds mesolytic cleavage mesomeric effect mesomerism mesomorphic phase mesomorphic state mesomorphic transition mesopause in atmospheric chemistrymesophase mesophase pitch mesophase pitch-based carbon fibres mesophiles mesopore in catalysismesoscale mesosphere messenger RNA metabolic half-life metabolism metabolite metal distribution metal to ligand charge transfer (MLCT) transition metal to metal charge transfer (MMCT) transition metal–carbene complexes metal–carbyne complexes metal–insulator transition metal–nonmetal transition metallacycloalkanes metallocenes metalloenzyme metallurgical coke metamagnetic transition metastability metastable metastable film metastable ion in mass spectrometrymetastable state in nuclear chemistrymetastable state in spectrochemistrymetatectoid reaction metathesis methanogens method of isotopic perturbation methylene methylidyne methylotrophic microorganisms metre \(\text{m}\)micellar catalysis micellar mass micellar solubilization micellar weight micelle micelle charge Michaelis constant \(K_{\text{m}}\)Michaelis–Menten kinetics Michaelis–Menten mechanism micro micro-network microbial leaching microcanonical rate constant microcanonical variational transition-state theory microcarrier in biotechnologymicroclimatology microdomain morphology microelectrophoresis microfiltration microgel microheterogeneity in biochemistrymicrometeorology microphotometer micropore filling in catalysismicropore in catalysismicropore volume in catalysismicroporous carbon microscopic chemical event microscopic cross-section \(\sigma\)microscopic diffusion control microscopic electrophoresis microscopic film microscopic kinetics microscopic reversibility at equilibrium microsome microsyneresis middle atmosphere Mie scattering migration migration current migration time \(t_{\text{m}}\) in capillary electrophoresismigration time of micelles \(t_{\text{mc}}\) in micellar electrokinetic chromatographymigratory aptitude migratory insertion milli milligram equivalent of readability of a precision balancemillimetre of mercury milling minimum consumption time \(t_{\text{min}}\) in flame emission and absorption spectrometryminimum density of states criterion minimum lethal concentration \(\text{LC}_{\text{min}}\)minimum lethal dose \(\text{LD}_{\text{min}}\)minimum-energy reaction path minus minute of arcmiscibility miscibility gap mist in atmospheric chemistrymitochondria mitosis mixed ceramic mixed control mixed crystal mixed energy release mixed indicator mixed labelled mixed potential mixing control mixing height in atmospheric chemistrymixing in analytical chemistrymixing ratio in analytical chemistrymixture MLCT mobile adsorption mobile phase in chromatographymobile-phase velocity \(u\) in chromatographymobility (general) mobility in aerosol physicsmobility \(\mu\)Möbius aromaticity mode mode-locked laser model network moderation in nuclear chemistrymoderator modified active solid in chromatographymodified Arrhenius equation modified sample modifier in solvent extractionmodulus of elasticity \(E\)Mohr amplification process in analysismoiety MOL file format molal molality \(m\),\(b\)molar molar absorption coefficient \(\varepsilon\)molar absorptivity molar activity in radiochemistrymolar average velocity molar conductivity molar refraction \(R\)molar-mass exclusion limit in polymersmolarity mole mole fraction molecular anion molecular beams molecular cation molecular conformation of a polymermolecular connectivity index molecular design molecular dynamics molecular dynamics in drug designmolecular entity molecular formula molecular graph molecular graph theory molecular graphics molecular ion in mass spectrometrymolecular kinetics molecular laser molecular mechanics calculation molecular metal molecular modeling molecular nucleation in polymersmolecular orbital molecular orientation molecular rearrangement molecular Rydberg state molecular shape molecular sieve effect molecular spectra molecular weight molecular-weight exclusion limit in polymersmolecularity molecule molfile molozonides moment of a force \(M\)moment of inertia \(I\),\(J\)momentum spectrum momentum \(p\)monitoring mono-energetic radiation monochromator monoclonal antibodies monodisperse medium monodisperse polymer monoisotopic mass spectrum monolayer monolayer capacity monolith monomer monomer molecule monomer unit monomeric unit monosaccharides monotectic reaction monotectoid reaction monotectoid temperature monoterpenes monoterpenoids monothioacetals monotropic transition Monte Carlo (MC), method of Monte Carlo study mordant More O'Ferrall–Jencks diagram Morin transition morphology morphology coarsening morphotropic transition Morse potential Mössbauer effect Mössbauer thickness in Mössbauer spectroscopymost probable distribution (in macromolecular assemblies) Mott transition Mott–Hubbard transition MPP-based carbon fibres mucopolysaccharides Mulliken population analysis multi-centre bond multi-centre reaction multi-channel pulse height analyser multi-strand chain in polymersmulti-strand macromolecule multicoat morphology multiconfiguration SCF method multident multienzyme multienzyme complex multienzyme polypeptide multilayer multilayer adsorption multilayer aggregate in polymer crystalsmultiphase copolymer multiphoton absorption multiphoton ionization in mass spectrometrymultiphoton process multiple inclusion morphology multiple ionization satellite multiple peak scanning in mass spectrometrymultiple scattering multiple-pass cell in spectrochemical analysismultiplex spectrometer multiplicative name multiplicity multiply labelled multipole line in X-ray spectroscopymultireference configuration interaction multistage sampling multivariate statistics munchnones muonium mustard oils mustards mutagen mutagenesis mutarotation mutation mutation rate in biotechnologymutual inductance \(M\)Myelin cylinders µ- (mu) in inorganic nomenclature
ångström n → π* state n → π* transition n → σ* transition n-star macromolecule n-strand chain n-strand molecule N-terminal residue n-σ* delocalization nano nanocomposite nanodomain morphology nanofiltration nanogel nanoscopic film naphthenes naphthenic acids narcissistic reaction natural atomic orbital natural bond orbital natural broadening of a spectral linenatural graphite natural hybrid orbital natural isotopic abundance natural lifetime natural orbital natural population analysis natural radiation natural radioactivity neat soap necrosis needle coke negative adsorption negative feedback negative hyper-conjugation negative ion in mass spectrometrynegaton neighbouring group participation nematic phase nematic state neodymium laser neoflavonoids neolignans neper nephelometry Nernst's diffusion layer net current net electric charge \(z\) of a particlenet in surface chemistrynet shaping network network defect network in polymer chemistrynetwork polymer network-chain molar mass \(M_{\text{c}}\)neutral-density filter neutralized gel neutrino neutron neutron density neutron multiplication neutron number \(N\)neutron rest mass neutron temperature neutrophilic organisms Newman projection newton Newton black film Newton diagram Newtonian fluid NHOMO nido- Nier–Johnson geometry NIH shift nimbostratus cloud in atmospheric chemistrynitramines nitrenes nitrenium ions nitrification nitrile imides nitrile imines nitrile oxides nitrile sulfides nitrile ylides nitriles nitrilimines nitrilium betaines nitrilium ions nitrimines nitro compounds nitrogen fixation nitrogen laser nitrogen mustards nitrogen ylides nitrolic acids nitrones nitronic acids nitrosamides nitrosamines nitrosimines nitroso compounds nitrosolic acids nitroxides nitroxyl radicals no carrier added no observed adverse effect level no-bond resonance no-load indication (for a precision balance) no-observed-effect-level nodal plane noise nominal linear flow \(F\) in chromatographynominally labelled tracer non-calorimetric thermophysical measurements non-coherent source non-crossing rule non-crystalline electrodes non-destructive activation analysis non-diagram line non-dissociative chemisorption non-draining non-equilibrium reaction non-graphitic carbon non-graphitizable carbon non-ideal chromatography non-ideal, linear chromatography non-ideal, non-linear chromatography non-isotopic labelling non-Kekulé molecules non-linear chromatography non-linear distribution isotherm in chromatographynon-linear optical effect non-linear optical polymer non-linear optical techniques non-linearity error in spectrochemical analysisnon-localized adsorption non-polarized interphases non-radiative decay non-specific adsorption non-uniform corrosion non-uniform polymer non-vertical energy transfer nonadiabatic nonadiabatic coupling nonadiabatic electron transfer nonadiabatic photoreaction nonbonded interactions nonbonding molecular orbital nonclassical carbocation nonclassical structure nonselective detector nonselective quantum counter nonselectively labelled nor- normal normal distribution normal kinetic isotope effect normal region (for electron transfer) normal stress \(\sigma\)normal X-ray level normal-phase chromatography normalization Norrish Type I photoreaction Norrish Type II photoreaction Norrish–Yang reaction nth order phase transition nuclear atom nuclear chemistry nuclear decay nuclear disintegration nuclear fission nuclear fuel nuclear fusion nuclear fusion reaction nuclear graphite nuclear isomers nuclear level nuclear magneton nuclear particle nuclear quadrupole moment (spectroscopic) nuclear reactor nuclear transformation nuclear transition nuclearity nucleating agent nucleation and growth nucleation in colloid chemistrynucleation of phase separation in polymer chemistrynucleic acids nucleofuge nucleon nucleon number nucleophile nucleophilic aromatic photosubstitution nucleophilic catalysis nucleophilicity nucleoproteins nucleosides nucleotide bases nucleotides nucleus nuclide nuclidic mass nuisance threshold in atmospheric chemistrynumber concentration \(C\),\(n\)number content \(\frac{N_{\text{B}}}{m}\)number density \(n\)number flow rate \(q_{\text{N}}\)number fraction number of entities \(N\)number of moles number of theoretical plates number-distribution function numerical value of a quantity
observation height \(h_{\text{obs}}\) in flame emission and absorption spectrometryobservation pathlength \(l_{\text{obs}}\) in flame emission and absorption spectrometryobservation space in flame emission and absorption spectrometryobservation volume \(V_{\text{obs}}\) in flame emission and absorption spectrometryobserved rate coefficient occlusion (molecular) octahedro- in inorganic nomenclatureodd-electron ion optically detected magnetic resonance odour threshold in atmospheric chemistryohm OLED olefins oligo oligomer oligomer molecule oligomeric oligomerization oligonucleotides oligopeptides oligosaccharides one-bond-flip one-colour indicator one-photon photochromism onion morphology onium compounds open atomizer open dynamic system open film open hearth furnace in atmospheric chemistryopen static system open-shell systems open-tubular column in chromatographyoperational pH cell operational pH standard operator gene operon opposing reactions optical activity optical antipodes optical density optical filter optical isomers optical multi-channel analyser optical parametric amplification optical parametric oscillator optical purity optical resolution optical rotation optical rotatory power optical spectroscopy optical yield optical-beam error in spectrochemical analysisoptically active polymer optically labile optoacoustic spectroscopy orbital (atomic or molecular) orbital energy orbital steering orbital symmetry order of reaction \(n\)order parameter order–disorder transition ordered co-continuous double gyroid morphology organelles organic dye laser organic–inorganic polymer organically modified silica organically-modified ceramic organo- organoheteryl groups organometallic compounds organyl groups origin of replication ortho acids ortho amides ortho esters ortho- and peri-fused (polycyclic compounds) ortho-fused (polycyclic compounds) orthokinetic aggregation in colloidsosazones oscillating reaction oscillator strength \(f_{ij}\)osmolality \(m\)osmolarity osmotic coefficient \(\phi\)osmotic concentration \(c\)osmotic pressure \(\mathit{\Pi}\)osones osotriazoles Ostwald ripening out-isomer out-of-plane bending coordinate in molecular geometryouter electric potential \(\psi\)outer Helmholtz plane outer-sphere electron transfer outgassing of a catalystoutput rate overall activation energy overlap integral \(S_{\text{rs}}\)overpotential \(\eta\)oxa-di-π-methane rearrangement oxenium ions oxidant in atmospheric chemistryoxidation oxidation number oxidation state oxidation–reduction (redox) titration oxidative addition oxidative coupling oxide network oxidized species oxidoreductases oxime O-ethers oximes oxo acids oxo carboxylic acids oxo compounds oxoacids oxocarbons oxonium ions oxonium ylides oxyacid oxygen-flask combustion in spectrochemical analysisoxylium ions ozone hole ozonides σ-orbital
P, M packed column in chromatographypacking in column chromatographypaddlanes pair attenuation coefficient in nuclear chemistrypair correlation length \(\xi\) in thin filmspair production in nuclear chemistryPallmann effect PAN-based carbon fibres paraffin parallel reactions parallel-chain crystal in polymersparamagnetic parametric amplification parametric processes parent hydride parent ion in mass spectrometryPariser–Parr–Pople (PPP) method partial anodic (cathodic) current partial charge exchange reaction partial charge transfer reaction partial decay constant in nuclear chemistrypartial digestion in spectrochemical analysispartial isotherm in surface chemistrypartial kinetic current in electrochemistrypartial least squares partial mass density \(\rho_{\text{B}}\)partial microscopic diffusion control partial molar Gibbs energy partial molar quantity partial order of reaction partial pressure partial rate factor partial specific volume \(v_{\text{B}}\)partially draining particle concentration in atmospheric chemistryparticle density in nuclear chemistryparticle induced X-ray emission analysis particle scattering factor particle scattering function particle size distribution in atmospheric chemistryparticle size in atmospheric chemistryparticular property particulate carbon particulate gel particulate matter in atmospheric chemistryparticulate sol partition partition chromatography partition coefficient partition constant \(K_{\text{D}}^{\text{o}}\)partition function partition isotherm in chromatographypartition ratio \(K_{\text{D}}\)partly open film pascal passivation in electrochemical corrosionpassivation potential in electrochemical corrosionpassive metal passive sampler passive state in electrochemical corrosionPaterno–Büchi reaction pattern recognition paucidisperse system Pauli exclusion principle PDMR peak analysis peak area in chromatographypeak area method peak base in chromatographypeak concentration (trace atmospheric component) peak current peak elution volume (time) \(\bar{V}_{\text{R}}\),\(\bar{t}_{\text{R}}\) in column chromatographypeak enthalpimetry peak fitting peak height in chromatographypeak in chromatographypeak maximum in chromatographypeak potential peak resolution \(R_{\text{s}}\) in chromatographypeak widths in chromatographypectins Peierls distortion Peierls transition pellicular packing in chromatographypenams pendant chain pendant group penems penetrant penetration depth penicillins Penning gas mixture pentads in polymerspentaprismo- peptides peptidoglycan peptization peptization per acids percent percent diastereoisomer excess percent enantiomer excess percentage error percentage exposed in metallic catalystspercentage relative error \(e_{\text{r}}\, (\%)\)percentage standard deviation \(s_{\text{r}}\, (\%)\),\(\sigma_{\text{r}}\, (\%)\)perfect network perfectly polarized interphase perfusion stationary phase (material) in liquid chromatographypericyclic reaction perikinetic aggregation in colloidsperiod \(T\)periodic copolymer periodic copolymerization periodic voltage peripheral atom in organic reaction mechanismsperiplanar periselectivity peritectic reaction peritectoid reaction peritectoid temperature permanent crosslink permeability of vacuum \(\mu_{0}\)permeability \(\mu\)permeate permeation chromatography permeation tube permittivity of vacuum permittivity \(\varepsilon\)permselectivity peroxides peroxisome peroxo compounds peroxy acids perpendicular effect persistence length in polymerspersistent perspective formula perstraction perturbation theory perturbed dimensions in polymerspervaporation pesticide pesticide residue peta petroleum coke petroleum pitch pH pH glass electrode pH gradient in electrophoresispH standard pH-rate profile pH0.5 or pH1/2 in solvent extractionphantom chain behaviour pharmacodynamics pharmacokinetics phase phase domain phase fluorimetry phase I reaction of biotransformationphase II reaction of biotransformationphase interaction phase inversion phase ratio \(\beta\) in chromatographyphase ratio \(r\) in liquid-liquid distributionphase rule phase separation phase transition phase-space theory phase-transfer catalysis phenolates phenols phenomenological equation phenonium ions phenotype phenoxides pheromone phonon phosphanes phosphanylidenes phosphatidic acids phosphazenes phosphine oxides phosphines phosphinic acids phosphinidenes phosphinous acids phospho phosphoglycerides phospholipids phosphonic acids phosphonitriles phosphonium compounds phosphonium ylides phosphono phosphonous acids phosphoramides phosphoranes phosphoranyl radicals phosphorescence phosphorescence lifetime phosphorimetry phosphoroscope phosphorus ylides phosphorylation phosphylenes photo-Bergman cyclization photo-Claisen rearrangement photo-elastic polymer photo-Fries rearrangement photoacoustic detector photoacoustic effect photoacoustic spectroscopy photoadsorption photoaffinity labelling photoassisted catalysis photobiology photocatalysis photocatalyst photocatalytic cell photochemical curing photochemical detector photochemical equivalence photochemical funnel photochemical hole burning photochemical nitrogen extrusion photochemical reaction photochemical reaction path photochemical smog photochemical yield photochemistry photochromism photoconductive detector photoconductivity photocrosslinking photocurrent yield photocyclization photocycloaddition photodecarbonylation photodecarboxylation photodeconjugation photodegradation photodesorption photodetachment of electronsphotodiode photodiode array photodynamic effect photoelectric attenuation coefficient photoelectric detector photoelectric peak photoelectrical effect photoelectrochemical cell photoelectrochemical etching photoelectrochemistry photoelectrolytic cell photoelectron spectroscopy photoelectron yield photoemissive detector photoexcitation photogalvanic cell photohydration photoimaging photoinduced electron transfer photoinduced polymerization photoinitiation photoionization photoionization detector in gas chromatographyphotoisomerization photoluminescence photoluminescent polymer photolysis photometry photomultiplier tube photon photon activation photon counting photon echo photon emittance photon exitance \(M_{\text{p}}\)photon exposure \(H_{\text{p}}\)photon flow \(\mathit{\Phi} _{\text{p}}\)photon fluence rate \(E_{\text{p,o}}\)photon fluence \(H_{\text{p,o}}\),\(F_{\text{p,o}}\)photon flux \(q_{\text{p}}\),\(\mathit{\Phi} _{\text{p}}\)photon irradiance \(E_{\text{p}}\)photon number \(N_{\text{p}}\)photon quantities photon radiance \(L_{\text{p}}\)photooxidation photooxygenation photopeak photophoresis photophosphorylation photophysical processes photopolymerization photoreaction photorearrangement photoreduction photoresist photoselection photosensitive polymer photosensitization photosensitizer photostationary state photosynthesis photosystem photothermal effect photothermography phototransistor photovoltaic cell phthaleins phthalides physical adsorption physical network physical quantity physisorption phytotoxicant pico picrates piezoelectric polymer piezoluminescence pile-up in radioanalytical chemistryPIN diode PIN semiconductor detector pinacols pinocytosis pitch pitch-based carbon fibres pitting corrosion Pitzer strain planar chirality planar chromatography planar film planar intramolecular charge transfer planar stereoisomerism Planck constant \(h\)plane angle plasma in biologyplasma desorption ionization in mass spectrometryplasma in spectrochemistryplasmid plastic flow plastic transition plate height \(H_{\text{eff}}\) in chromatographyplate number \(N\) in chromatographyplateau border in surface chemistryPLED pleiotropic gene ploidy plug-flow in catalysisplumbylenes plumbylidenes plume in atmospheric chemistryplus, minus pneumatic detector point group point of zero charge poise poison in catalysisPoisson distribution polar aprotic solvent polar effect polar solvent polarity polarizability polarization error in spectrochemical analysispolarization \(\zeta\) in electrochemistrypolarization \(P\)polarized interphases polarography polaron pollution (pollutant) pollution rose polyacid polyaddition polybase polybetaine polychromator polycondensation polycrystalline graphite polycyclic system polydent polydisperse medium polydisperse polymer polyelectrolyte polyelectrolyte complex polyelectrolyte gel polyelectrolyte network polyfunctional catalysis polygranular carbon polygranular graphite polyhedral symbol polyhedranes polyions polyketides polymer polymer alloy polymer blend polymer catalyst polymer compatibilizer polymer complexation polymer composite polymer crystal polymer crystallite polymer cyclization polymer degradation polymer drug polymer functionalization polymer gel polymer membrane polymer molecule polymer network polymer phase-transfer catalyst polymer reactant polymer reaction polymer solvent polymer sorbent polymer support polymer surfactant polymer-derived ceramic polymer-metal complex polymer-poor phase polymer-rich phase polymer-supported catalyst polymer-supported reaction polymer–polymer complex polymer–solvent interaction polymerase chain reaction polymeric polymeric inner salt polymeric sol polymeric stationary phase (material) in liquid chromatographypolymerization polymolecularity correction polymorphic transition polypeptides polyprenols polyquinanes (polyquinenes) polysaccharides polysulfanes polysulfides polytopal rearrangement polytypic transition pooled relative standard deviation pooled standard deviation population inversion pore size distribution Porod–Kratky chain porosity porous-layer open-tabular (PLOT) column in chromatographyporphyrinogens porphyrins position-sensitive photomultiplier tube positive feedback positive ion in mass spectrometrypositron positronium post-column derivatization in chromatographypost-filter effect in luminescence spectroscopypostprecipitation potential at the point of zero charge (p.z.c.) potential energy \(E_{\text{p}}\),\(V\)potential of a cell reaction potential temperature potential-determining (p.d.) ions potential-energy (reaction) surface potential-energy profile potentiation potentiometer potentiometric detection method in electrochemical analysispotentiometric selectivity coefficient power level power \(P\)pre-association pre-equilibrium in solvent extractionpre-equilibrium (prior equilibrium) pre-exponential factor \(A\)pre-filter effect in luminescence spectroscopypre-gel regime pre-gel state pre-polymer pre-polymer molecule pre-reactive complexes precipitation precipitation fractionation of polymersprecipitation from homogeneous solution in analysisprecipitation in sol-gel processingprecipitation titration precision precision of a balanceprecision of a weighingprecision of indication of a balancepreconcentration coefficient of a desired microcomponentpreconcentration in trace analysisprecursor complex precursor in radioanalytical chemistryprecursor ion in mass spectrometrypredissociation preferential sorption in polymerspremium coke premix burner in flame spectroscopyprenols prepolymer prepreg pressure flow pressure gradient correction factor in gas chromatographypressure jump pressure-induced transition pressure-sensitive detector pressure \(p\)pretreatment of a catalystprimary (photo)process primary (photo)product primary crystallization primary current distribution primary electrons in in situ microanalysisprimary excitation primary isotope effect primary kinetic electrolyte effect primary kinetic isotope effect primary mixture primary particle primary pH standards primary photochemical process primary pollutant in atmospheric chemistryprimary sample primary standard primary structure primary structure of a segment of a polypeptideprimitive change principal group principal ion in mass spectrometryprincipal moments of inertia principle of least nuclear motion principle of microscopic reversibility principle of minimum structural change prior distribution \(P_{0}\)prior equilibrium priority pro-E, pro-Z pro-R, pro-S probability density \(P\)probability \(P\)probe in biotechnologyprocess prochirality prochirality centre product product development control product ion product state distribution product-determining step productivity \(r\) in biotechnologyprogenitor ion in mass spectrometryprogram programmed-flow chromatography programmed-pressure chromatography programmed-temperature chromatography projection formula prolate trochoidal mass spectrometer promoter (gene technology) promoter in catalysispromotion prompt coincidence prompt neutrons propagating reaction propagation propellanes property prophage proportional counter proportional counter tube proportional gas-scintillation counter proprochirality pros in histidine nomenclatureprostaglandins prostanoids prosthetic group proteases protected lyophobic colloid protection of a reactive group protective action in colloid chemistryprotein engineering proteins proteoglycan proteome protic protide protio protium protogenic (solvent) protolysis proton proton affinity proton charge proton magnetic moment proton magnetogyric ratio proton number proton rest mass proton transfer reaction protonated molecule in mass spectrometryprotonation constant protophilic (solvent) protoplast prototrophs prototropic rearrangement pseudo acids pseudo bases pseudo rate constant pseudo-asymmetric carbon atom pseudo-axial pseudo-catalysis pseudo-co-oligomer pseudo-copolymer pseudo-equatorial pseudo-first-order rate coefficient pseudo-first-order reaction pseudo-unimolecular pseudo-zero-order reaction pseudohalogens pseudomolecular rearrangement pseudopericyclic pseudorotation pseudoureas psychosine psychrometric hygrometer psychrometry puffing puffing inhibitor pulsatance pulse amplitude analyser pulse amplitude selector pulse duration in electroanalytical chemistrypulse height analyser pulse reactor in catalysispump-dump-probe technique pump-probe technique purine bases pyramidal inversion pyranoses pyrimidine bases pyro pyroelectric detector pyrolysis pyrolysis-gas chromatography pyrolytic carbon pyrolytic graphite pyrromethenes π – π* state π → π* transition π-complex
Q-switched laser QSAR quadratic mean \(\bar{x}_{q}\)quadro- quadrupole ion storage trap quadrupole mass analyser quadrupole splitting in Mössbauer spectroscopyqualitative analysis qualitative elemental specificity in analysisquality assurance quality control quality factor in nuclear analytical chemistryquality of solvent in polymer chemistryquantitative analysis quantitative structure–activity relationship in drug designquantitative structure–activity relationships quantity quantity calculus quantity of dimension one quantized internal energy quantum counter quantum efficiency quantum mechanics/molecular mechanics quantum of radiationquantum well multilayer quantum yield \(\mathit{\Phi}\)quantum-mechanical tunnelling quarter-transition-time potential quartet state quartz–iodine lamp quasi-axial quasi-classical trajectory (QCT) method quasi-enantiomers quasi-equatorial quasi-equilibrium quasi-molecular ion in mass spectrometryquasi-racemic compound quasi-single-strand polymer quaternary ammonium compounds quaternary structure quaterpolymer quencher quenching quenching constant in photochemistryquenching correction in photochemistryquinarenes quinhydrones quinomethanes quinomethides quinone diazides quinones quinonimines quinonoximes Quistor γ-quantum θ state in polymers
(chain) repeating distance (vertical) rise velocity \(v_{\text{f}}\) in flame emission and absorption spectrometryR, S r, s R*, S* rabbit rac racemate racemic racemic compound racemic conglomerate racemic mixture racemization racemo structures in polymersrad radial development radial electrostatic field analyser in mass spectrometryradial elution (radial development) or circular elution (circular development) in planar chromatographyradian radiance \(L\)radiant (energy) flux \(P\),\(\mathit{\Phi}\)radiant emittance radiant energy density \(\rho\),\(w\)radiant energy \(Q\)radiant exitance \(M\)radiant exposure \(H\)radiant flux radiant intensity \(I\)radiant power \(P\)radiant quantities radiation radiation chemistry radiation constants radiation continuum in spectrochemistryradiation counter radiation detector radiation hazard radiation reaction radiation spectrum radiation trapping radiationless deactivation radiationless transition radiative absorption in spectrochemistryradiative capture radiative de-excitation in spectrochemistryradiative energy transfer radiative lifetime \(\tau_{0}\)radiative transition radical (free radical) radical anion radical cation radical centre(s) radical combination radical copolymerization radical disproportionation radical ion radical pair radical photosubstitution radical polymerization radicofunctional name radioactive radioactive age radioactive chain radioactive contamination radioactive cooling radioactive dating radioactive decay radioactive equilibrium radioactive fallout radioactive half life radioactive series radioactive source radioactive tracer radioactive tracer technique in analysisradioactive waste radioactivity radioanalytical chemistry radiochemical activation analysis radiochemical purification radiochemical purity radiochemical separation radiochemical yield radiochemistry radiochromatograph radiocolloid radioenzymatic assay radiograph radiogravimetric analysis radioimmunoassay radioiodination radioisotope radioisotope dilution analysis radioisotope induced X-ray emission analysis radioluminescence radiolysis radiometric analysis radiometric titration radiometry radionuclide radionuclidic purity radioreceptor assay radiorelease analysis radiosonde radius of gyration \(s\)raffinate rain out in atmospheric chemistryrandom coil in polymersrandom coincidence in nuclear chemistryrandom copolymer random copolymerization random error random sample range in analysisrange of measurement of an analyserRaoult's law rate rate coefficient rate constant \(k\)rate law rate of appearance rate of change of a quantity rate of change ratio rate of consumption \(\nu_{n\text{,B}}\),\(\nu_{c\text{,B}}\)rate of conversion \(\dot{\xi}\)rate of disappearance rate of fluid consumption \(q_{\text{V}}\) in flame emission and absorption spectrometryrate of formation \(\nu _{n\text{,y}}\),\(\nu_{\text{c,y}}\)rate of liquid consumption in flame spectroscopyrate of migration \(v\) in electrophoresisrate of nucleation rate of reaction \(\nu\)rate-controlling step rate-determining step ratemeter in radiochemistryratio raw coke Rayleigh ratio Rayleigh scattering rayon-based carbon fibres re-extraction Re, Si reactance \(X\)reactant reacting bond rules reaction reaction barrier reaction chromatography reaction coordinate reaction cross-section \(\sigma_{\text{r}}\)reaction dynamics reaction injection moulding reaction intermediate reaction mechanism reaction path reaction path degeneracy reaction probability \(P_{\text{r}}\)reaction stage reaction step reaction time reactive (reactivity) reactive adsorption reactive blending reactive complex reactive desorption reactive polymer reactive polymer processing reactive scattering reactivity index reactivity–selectivity principle readability of a balancereading reagent real (electrified) interphase real potential of a species in a phase real surface (interface) area rearrangement rearrangement ion in mass spectrometryrearrangement stage rebound reaction receptor receptor in drug designrecognition site recoil in radioanalytical chemistryrecoil labelling recoil-free fraction in Mössbauer spectrometryrecombinant DNA technology recombination fluorescence reconstructive transition recovery recovery factor in an extraction processrecrystallization red shift redox ion exchangers redox polymer redox potential reduced adsorption reduced limiting sedimentation coefficient reduced mass \(\mu\)reduced mobile phase velocity \(\nu\) in chromatographyreduced osmotic pressure reduced sample reduced sedimentation coefficient reduced species reduced viscosity of a polymerreducing in analytical chemistryreduction reductive elimination reductones referee sample reference atom in organic reaction mechanismsreference cell reference dose reference electrode reference material reference method reference procedure in analysis of trace air constituentsreference state of an elementreference value pH standard reflectance \(\rho\)reflection electron energy loss spectroscopy reflection factor reflection high energy electron diffraction refraction effects refractive index increment in polymer chemistryrefractive index \(n\)regeneration of a catalystregioselectivity (regioselective) regression analysis regular block in a polymerregular coke regular comb macromolecule regular macromolecule regular oligomer molecule regular polymer regular single-strand polymer regular star macromolecule regulator gene Rehm–Weller equation reinforced reaction injection moulding Reissert compounds rel relative relative activity relative adsorption relative atomic mass \(A_\text{r}\)relative biological effectiveness of radiationrelative configuration relative counting in nuclear chemistryrelative density \(d\)relative detection limit relative electrode potential relative elongation relative error relative hardness relative humidity relative local current density relative micellar mass relative molar mass relative molecular mass \(M_{\text{r}}\)relative permeability \(\mu_{\text{r}}\)relative permittivity \(\varepsilon_{\text{r}}\)relative preconcentration in trace analysisrelative responsivity relative retardation \(R_{\text{rel}}\) in planar chromatographyrelative retention \(r\) in column chromatographyrelative selectivity in catalysisrelative spectral responsivity relative standard deviation \(s_{\text{r}}\),\(\sigma_{\text{r}}\)relative uncertainty relative viscosity relative viscosity increment relative volumic mass relativistic effects relaxation relaxation kinetics relaxation time releaser in analytical flame spectroscopyrem Renner–Teller effect reorganization energy in electron transferreorganization in polymersrepeatability repeating distance repetency replacement name replacement operation in organic nomenclaturereplicate (duplicate) sample replication report in analysisreprecipitation representative sample repression reproducibility repulsive potential-energy surface reserve sample residence time residence time \(t_{\text{r}}\) in biotechnologyresidual current residual emission anisotropy residual fuel/oil residual liquid junction (potential) error in pH measurementresidual spectrum/background spectrum in mass spectrometryresin resist polymer resistance \(R\)resistivity \(\rho\)resolution resolution in gas chromatographyresolution in optical spectroscopyresolution in stereochemistryresolving power in mass spectrometryresolving power \(R\) in optical spectroscopyresolving time correction in nuclear analytical chemistryresolving time in nuclear analytical chemistryresonance resonance absorption technique resonance broadening resonance cross-section in Mössbauer spectrometryresonance effect resonance effect magnitude in Mössbauer spectrometryresonance emission resonance energy resonance energy in radiochemistryresonance fluorescence resonance fluorescence technique resonance hybrid resonance integral in radiochemistryresonance integral \(H_{\text{rs}}\)resonance lamp resonance line in photochemistryresonance line in X-ray spectroscopyresonance neutrons resonance radiation response constant in electroanalytical chemistryresponse time of an analyserresponse time \(\tau_{\text{R}}\) of a radiation detectorresponsive gel responsivity \(R\) in detection of radiationrest point of a balancerestricted rotation restriction enzymes result in analysisretardation factor \(R\) in column chromatographyretardation factor \(R_{\text{F}}\) in planar chromatographyretarder retentate retention efficiency in particle separationretention factor \(k\) in column chromatographyretention in nuclear chemistryretention index \(I\) in column chromatographyretention of configuration retention temperature in chromatographyretention time in chromatographyretention volumes in chromatographyreticulation retinoids retro retro-ene reaction retroaddition retrocycloaddition reverse micelle reverse osmosis reverse transcriptases reversed (radiochemical) isotope dilution analysis reversed direct-injection burner in analytical flame spectroscopyreversed-phase chromatography reversible network reversible transition revolutions per minute RF value \(R_{\text{F}}\) in chromatographyrheology rheopexic gel rheopexy rhodamine dyes rhombohedral graphite ribbon delocalisation ribonucleic acids ribonucleotides ribosomal RNA ribosomes Rice–Ramsperger–Kassel (RRK) theory Rice–Ramsperger–Kassel–Marcus (RRKM) theory riffling in analytical chemistryrigid chain ring assembly ring reversal ring-opening copolymerization ring-opening polymerization ring-sector Ringelmann chart in atmospheric chemistryringing gel rise time rise time of an analyserrisk risk assessment risk estimation Ritchie equation RM value \(R_{\text{M}}\) in planar chromatographyRNA rod-like morphology röntgen root-mean-square end-to-end distance \(\text{<}r^{2}\text{>}^{1/2}\) in polymersRosanoff convention rotamer rotational barrier rotational constants rotational correlation time \(\tau_{\text{c}}\),\(\theta\)rotational diffusion rotational diffusion coefficient rotational frequency \(f_{\text{rot}}\) in centrifugationrotational relaxation time \(\rho\)rotational term \(F\)rotator phase transition rotatory power rotaxanes rotenoids rotometer in atmospheric chemistryroughness factor of a surfacerovibronic state Rp, Sp rRNA RS rubredoxin ruby laser rupture of a thin filmRutherford backscattering Rydberg constant Rydberg orbital Rydberg state Rydberg transition RYDMR α- (β-, γ-) ray spectrometer γ-radiation γ-ray spectrometer
S s-cis, s-trans saccharides Sackur–Tetrode constant sacrificial acceptor sacrificial donor sacrificial hyperconjugation saddle point salt salt effect salt form of an ion exchanger salting out sample error in spectrochemical analysissample handling in analysissample in analytical chemistrysample injector in chromatographysample unit sampler sampling error sampling interval in electroanalysissampling plan in analytical chemistrysampling time in electroanalysissandwich compounds sanitary land fill saprophyte saturated solution saturation saturation activity saturation capacity saturation fraction \(s_{\text{B}}\)saturation in radioanalytical chemistrysaturation loading saturation transfer saturation vapour pressure sawhorse projection Saytzeff rule sc scaler scaling circuit scaling factor scanning electron microscopy scanning method in mass spectrometryscanning transmission electron microscopy scattering scattering angle \(\theta\)scattering cross-section \(\sigma_{\text{scat}}\)scattering error in spectrochemical analysisscattering matrix scattering plane scattering vector scavenger scavenging in atmospheric chemistrySchenck reaction Schenck-sensitization mechanism Schiff bases Schiller layers Schottky-barrier photodiode Schulz–Zimm distribution Schulze–Hardy rule scintillation scintillation counter scintillation detector scintillation spectrometer scintillators scrambling scrubber in atmospheric chemistryscrubbing in atmospheric chemistryseco- second \(\text{s}\)second messenger second of arcsecond-order transition secondary crystallization secondary current distribution secondary electron multiplier in mass spectrometrysecondary electron yield in in situ microanalysissecondary electrons in in situ microanalysissecondary excitation secondary fluorescence in X-ray emission spectroscopysecondary ionization in mass spectrometrysecondary isotope effect secondary kinetic electrolyte effect secondary kinetic isotope effect secondary metabolites secondary pollution (emissions) secondary radiation secondary standard secondary structure secular equation secular equilibrium sediment sedimentation sedimentation coefficient \(s\)sedimentation equilibrium sedimentation field strength sedimentation in chemistrysedimentation potential difference sedimentation velocity method sedimentation velocity \(v_{\text{B}}\)sedimentation volume segment in analytical chemistrysegmented copolymer segregated star macromolecule segregation segregation in polymersselected area electron diffraction selected ion monitoring in mass spectrometryselection in biotechnologyselection rule selective corrosion selective detector selective digestion selective elution in chromatographyselective in analysisselective inhibition selective micro-sample in spectrochemical analysisselective poisoning in catalysisselective preconcentration in trace analysisselective sample selective solvent in polymer chemistryselective sorption selectively labelled selectivity selectivity selectivity coefficient \(k_{\text{A/B}}\) in ion exchange chromatographyselectivity factor in ion exchange chromatographyselectivity factor \(S_{f}\)selectivity of a reagentselectivity ratio selenenic acids selenides seleninic acids selenocyanates selenols selenones selenonic acids selenoxides self inductance \(L\)self-absorption self-absorption broadening of a spectral lineself-absorption effect in luminescence spectroscopyself-absorption factor of a radiation sourceself-diffusion coefficient self-localized excitations in conjugated organic polymersself-poisoning in catalysisself-quenching self-reversal self-shielding selones semi-empirical quantum mechanical methods semi-interpenetrating polymer network semi-rigid chain semicarbazones semicoke semiconductor semiconductor detector semiconductor laser semiconductor-metal transition semioxamazones semiquinones semisystematic name seniority (senior) in organic nomenclaturesensitive area of a radiation detectorsensitive volume of a radiation detectorsensitivity in mass spectrometrysensitivity \(A\) in metrology and analytical chemistrysensitization sensitization in colloid chemistrysensitized luminescence sensitizer separability assumption separated flame in flame spectroscopyseparation coefficient separation factor \(\alpha\) in column chromatographyseparation factor \(\alpha_{\text{A,B}}\) in liquid-liquid distributionseparation number \(\text{SN}\) in chromatographyseparation temperature in chromatographysequence sequence rules sequencing (proteins, nucleic acids) sequential analyser sequential indication of an analysersequential interpenetrating polymer network sequential measuring cell sequential sample sequential semi-interpenetrating polymer network sequential spectrometer series of analytical resultsserum sesquiterpenoids sesterterpenoids settling chamber in atmospheric chemistrysettling error in spectrochemical analysissettling velocity shape selectivity in catalysisshape-memory polymer shear breakdown shear dependent viscosity shear modulus \(G\)shear rate shear strain \(\gamma\)shear stress \(\tau\)shear thickening shear thinning shear transition shear viscosity shielded flame shielding shielding constant \(\sigma\)shish-kebab structure short chain short-chain branch short-range intramolecular interactions in polymersshrinkage shut-down state in analysisshut-down time in analysisshuttle vector SI Si sialon side chain side group side group or side-chain polymer liquid crystal siemens sievert sigmatropic rearrangement signal in analysissignal sequence silanes silanols silasesquiazanes silasesquioxanes silasesquithianes silathianes silazanes silicones siloxanes silver film silyl groups silyl radicals silylene simple shear simulation technique in analysissimultaneous interpenetrating polymer network simultaneous nucleation simultaneous pair transitions simultaneous reactions simultaneous semi-interpenetrating polymer network simultaneous spectrometer single cell protein single channel pulse height analyser single escape peak single photon counting single scattering single-beam (luminescence) spectrometer single-electron transfer mechanism single-focusing mass spectrometer single-photon timing single-step reaction single-strand chain in a polymersingle-strand macromolecule single-strand polymer singlet molecular oxygen singlet state singlet-singlet absorption singlet-singlet annihilation singlet-singlet energy transfer singlet-triplet absorption singlet-triplet energy transfer singlet–triplet crossing singly labelled sink in atmospheric chemistrysintering size-exclusion chromatography skeletal atom skeletal bond skeletal structure skew Slater determinant Slater-type orbital slip slip casting slot burner slow neutrons SM-interference small particle in radiation scatteringsmectic state SMILES smog chamber in atmospheric chemistrysmog in atmospheric chemistrysmog index in atmospheric chemistrysmoke smooth transition soap soap curd soap film soft acid soft base soft-segment phase domain soiling in atmospheric chemistrysol sol fraction sol-gel coating sol-gel critical concentration sol-gel material sol-gel metal oxide sol-gel process sol-gel silica sol-gel transition solar conversion efficiency solar flare solar radiation in atmospheric chemistrysolid angle \(\varOmega\),\(\omega\)solid phase antibody radioimmunoassay solid polymer electrolyte solid solution solid state lasers solid support in column chromatographysolid volume in column chromatographysolidification solidus soliton solubility solubility parameter \(\delta\)solubility parameter \(\delta\)solubility product solubilization solute solute-volatilization interference in flame spectroscopysolution solvation solvation energy solvatochromic relationship solvatochromism solvent solvent extraction solvent front in chromatographysolvent in liquid-liquid distributionsolvent ion exchange solvent isotope effect solvent migration-distance in chromatographysolvent parameter solvent regeneration in extraction processessolvent shift solvent-induced symmetry breaking solvent-separated ion pair solvent-shared ion pair solvolysis solvophobicity parameter \(Sp\)solvus SOMO sonication sonogel sonoluminescence sonosol soot Soret band sorption in colloid chemistrysorption isotherm in ion exchangesorption techniques in trace analysissorptive insertion in surface catalysissource efficiency sp space charge in a semiconductorspace formula space time in catalysisspace velocity in catalysisspacer spark (source) ionization in mass spectrometryspatial-distribution interference in flame spectroscopyspatially resolving detector of radiationspecial salt effect speciation analysis in chemistryspeciation in chemistryspecies (taxonomic) specific specific acid–base catalysis specific activity \(a\) in radiochemistryspecific adsorption specific burn-up specific catalysis specific conductance specific detector in chromatographyspecific gravity specific heat capacity \(c\)specific in analysisspecific ionization in nuclear chemistryspecific permeability in chromatographyspecific photon emission specific pore volume of a catalystspecific retention volume in chromatographyspecific surface area in surface chemistryspecific volume \(v\)specific weight specifically absorbing ion specifically labelled specifically labelled tracer specimen in analytical chemistryspectator mechanism spectator-stripping reaction spectral (photon) effectiveness spectral bandwidth error in spectrochemical analysisspectral distribution spectral fluence rate \(E_{\lambda,\text{o}}\)spectral intensity spectral interference in flame spectroscopyspectral irradiance \(E_{\lambda}\)spectral overlap spectral photon exitance \(M_{\text{p}\lambda}\)spectral photon flow \(\varPhi_{\text{p}\lambda}\)spectral photon flux \(E_{\text{p}\lambda}\)spectral photon radiance \(L_{\text{p}\lambda}\)spectral quantities spectral radiance \(L_{\lambda}\)spectral radiant energy \(Q_{\lambda}\)spectral radiant exitance \(M_{\lambda}\)spectral radiant flux spectral radiant intensity \(I_{\lambda}\)spectral radiant power \(P_{\lambda}\)spectral responsivity spectral responsivity function spectral sensitivity \(S(\lambda)\)spectral sensitization spectral spheradiance spectrochemical buffer in atomic spectroscopyspectrochemical carrier in atomic spectroscopyspectrogram spectrograph spectrometer spectrometry spectroscope spectroscopy spectrum analysis specular reflectance \(\rho\) in optical spectroscopyspeed distribution function \(F\left(c\right)\)speed of light in a vacuum \(c_{0}\),\(c\)speed \(\nu\),\(c\)spherical carbonaceous mesophase spherical radiance spherical radiant exposure spherulite spin adduct spin conservation rule spin contamination spin counting spin crossover spin density spin label spin polarization spin probe spin projection spin trapping spin-allowed electronic transition spin-flip method spin-flip transition spin-flop transition spin-glass transition spin-orbit coupling spin-orbit coupling constant \(A\)spin-orbit splitting spin-Peierls transition spin-state transition spin-statistical factor in diffusion-controlled reactionsspin–spin coupling spin–spin coupling constant \(J_{\text{AB}}\)spinodal spinodal decomposition spiro atom spiro chain in a polymerspiro compounds spiro macromolecule spiro polymer spiro union splicing of DNAspontaneous emission spontaneous fission spontaneous resolution spot in chromatographyspot sampling sprayer in flame spectroscopyspread monolayer spreading function in chromatographyspreading wetting sputter yield sputtering square-wave current SR stability constant stable stable film, metastable film stable ion in mass spectrometrystaggered conformation stagnant inversion in atmospheric chemistrystand-by state in analysisstandard acceleration of free fall standard atmosphere standard atomic weights standard chemical potential standard concentration standard conditions for gases standard deviation \(s\)standard electrode potential \(E^{\unicode{x26ac}}\)standard electromotive force standard entropy of activation \(\Delta ^{\ddagger}S^{\,\unicode{x26ac}}\),\(\Delta ^{\ddagger}S\)standard equilibrium constant \(K^{\unicode{x26ac}}\),\(K\)standard Gibbs energy of activation \(\Delta ^{\ddagger}G^{\,\unicode{x26ac}}\),\(\Delta ^{\ddagger}G\)standard hydrogen electrode standard molality \(m^{\unicode{x29B5}}\),\(m^{\,\unicode{x26ac}}\)standard potential of an electrode reaction standard potential of the reaction in a chemical cell standard pressure standard rate constant of an electrode reaction standard reaction quantities standard solution standard state standard subtraction method in electroanalytical chemistrystandard thermodynamic quantities standard uncertainty stannoxanes stannylenes stannylidenes star copolymer star macromolecule star polymer Stark effect start-up time in analysisstarting line in chromatographystarting point state crossing state diagram state function state-to-state kinetics static fields mass spectrometer static pressure static quenching static stability stationary phase (fermentation) stationary phase in chromatographystationary phase volume \(V_{\text{s}}\) in chromatographystationary state in kineticsstationary-phase fraction statistical coil statistical copolymer statistical copolymerization statistical factor statistical pseudo-copolymer statistical segment in polymersstatistical weight steady state steady state approximation steady state in liquid-liquid distributionStefan–Boltzmann constant stem cell stem in polymer crystalsstep height in chromatographystep in chromatographystepped surface stepwise elution in chromatographystepwise reaction steradian stereoblock macromolecule stereoblock polymer stereochemical formula stereochemical non-rigidity stereoconvergence stereodescriptor stereoelectronic stereoelectronic control stereoformula stereogenic unit stereoheterotopic stereohomosequence in a polymerstereoisomerism stereoisomers stereomutation stereoregular macromolecule stereoregular polymer stereorepeating unit in a polymerstereoselective polymerization stereoselective synthesis stereoselectivity stereosequence in a polymerstereospecific polymerization stereospecifically labelled tracer stereospecificity steric effect steric factor steric factor in polymerssteric hindrance steric isotope effect steric strain steric-approach control Stern layer Stern–Volmer kinetic relationships steroids sterols stibanes stibanylidenes stibines stibinidenes stibonium compounds sticking coefficient in surface chemistrysticking probability in surface chemistrysticky ends in biotechnologystimulated emission stirred flow reactor in catalysisstochastic effect stochastic sampling stochastic theories Stock number Stockholm convention stoichiometric stoichiometric capacity stoichiometric concentration \(c\)stoichiometric mean molal in electrochemistrystoichiometric number \(\nu\)stoichiometry stokes Stokes law Stokes number \(St\)Stokes parameters Stokes shift Stokes type radiation stopped flow stopped-flow cell in spectrochemical analysisstopping power STP strain strain energy strain-induced transition stratified film stratified sample stratocumulus cloud stratopause stratosphere stratus cloud stray radiation error in spectrochemical analysisstreak camera streak tube streaming birefringence streaming current streaming potential difference stress graphitization stress-assisted transition strip dynode photomultiplier tube stripping stripping isotherm stripping ratio in solvent extractionstripping reaction stripping solution in liquid-liquid distributionstrong collision structural disorder structural formula structural stability structural transition structure of a catalyststructure-based design in drug designstructure-property correlations structure–activity relationship styphnates subchain of a polymersubgroup-supergroup transition subjacent orbital sublation in solvent extractionsublimation subphase subsample substance concentration substance content \(n/m\)substance flow rate substance fraction \(x\)substituent atom (group) substituent electronegativity substitution reaction substitutive name substoichiometric extraction substoichiometric isotope dilution analysis substrate substrate substrate in thin filmssubtractive name successor complex sudden polarization sudden potential-energy surface sugars suicide inhibition suicide metabolism sulfamic acids sulfanes sulfatides sulfenamides sulfenes sulfenic acids sulfenium ions sulfenyl groups sulfenyl nitrenes sulfenyl radicals sulfenylium ions sulfides sulfilimines sulfimides sulfimines sulfinamides sulfinamidines sulfines sulfinic acids sulfinic anhydrides sulfinimines sulfinylamines sulfolipids sulfonamides sulfonamidines sulfonediimines sulfones sulfonic acids sulfonic anhydrides sulfonimides sulfonium compounds sulfonphthaleins sulfonylamines sulfoxides sulfoximides sulfoximines sulfur diimides sultams sultims sultines sultones sum of states \(P(\varepsilon)\)summit current in polarographysummit potential superabsorbent polymer superacid superbase superconducting transition supercritical drying of a gel supercritical fluid supercritical fluid chromatography superequivalent adsorption superexchange interaction superficial work in surface chemistrysuperlattice superposability superradiance supersaturation support of a catalystsupport plate in chromatographysupport-coated open-tubular (SCOT) column in chromatographysupporting electrolyte suppressor suprafacial supramolecular chemistry supramolecule surface surface (excess) conductivity surface active agent surface amount \(n^{\text{s}}\),\(n^{\text{a}}\)surface barrier semiconductor detector surface catalysis surface charge density \(\sigma\)surface charge layer surface chemical potential surface concentration \(\mathit{\Gamma}\)surface contamination in surface analysissurface coverage \(\theta\)surface crossing surface density \(\rho_{\text{A}}\),\(\rho_{\text{S}}\)surface dilatational viscosity surface dipole layer surface electric potential surface excess concentration \(\mathit{\Gamma}\)surface excess energy surface excess enthalpy surface excess entropy surface excess Gibbs energy surface excess Helmholtz energy surface excess isotherm surface excess \(n^{\sigma}\)surface fractal dimension surface grafting surface ionization in mass spectrometrysurface ions surface layer surface of a phase surface of tension surface potential surface pressure surface reaction surface region surface rheology surface shear viscosity surface states surface stress \(T_{ij}\)surface tension \(\gamma\),\(\sigma\)surface work surfactant surprisal analysis surprisal \(s\)suspended matter in atmospheric chemistrysuspension suspension effect in an ion-selective electrodeSwain–Lupton equation Swain–Scott equation swelling agent swelling in colloid and surface chemistryswelling pressure in colloid and surface chemistryswitchboard model in polymer crystalsswitching transition sydnone imines sydnones sym- symbiosis symbol in quantities and unitssymmetrical films symmetry number \(s\)symmetry-breaking transition symmetry-conserving transition symproportionation syn synartetic acceleration synchronization (principle of nonperfect synchronization) synchronous synchronously excited (fluorescence, phosphorescence) spectrum synchrotron radiation synclinal syndet syndiotactic macromolecule syndiotactic polymer syndiotactic triads in polymerssyneresis synergism in solvent extractionsynergism in toxicologysynoptic scale synperiplanar syntectic reaction synthetic graphite system system of units of measurementsystematic error systematic name Système International d'Unités systemic effect Szilard–Chalmers effect π → σ* transition σ → σ* transition σ, π (sigma, pi)
'true' rate constant T-jump tactic block in a polymertactic block polymer tactic macromolecule tactic polymer tacticity Taft equation tagged tailing in chromatographytandem mass spectrometer target in biologytautomeric effect tautomerism tautomerization tele tele-substitution telechelic molecule telechelic polymer tellurides tellurones telomer telomerization temperature temperature coefficient of responsivitytemperature effect in luminescence spectroscopytemperature inversion in atmospheric chemistrytemperature jump temperature lapse rate in atmospheric chemistrytemperature-programmed chromatography template in biotechnologytemporary poisoning in catalysistera term in X-ray spectroscopyterm symbols term \(T\)termination terminator in biotechnologytermolecular terpenes terpenoids terpolymer tertiary current distribution tertiary structure tesla test portion test sample test solution in analysistetracyclines tetrads tetrahedral intermediate tetrahedro- tetrapyrroles tetraterpenoids texture of a catalysttheoretical ceramic yield theoretical plate number thermal analysis thermal black thermal column in nuclear chemistrythermal conductance \(G\)thermal conductivity detector in gas chromatographythermal conductivity \(\lambda\)thermal curing thermal detector thermal fission thermal ionization in mass spectrometrythermal lensing thermal neutrons thermal resistance \(R\)thermally activated delayed fluorescence thermally-induced transition thermoacoustimetry thermochemical analysis thermochemical calorie thermochromism thermocouple thermodilatometry thermodynamic control of product compositionthermodynamic energy thermodynamic equilibrium constant thermodynamic isotope effect thermodynamic quality of solvent in polymer chemistrythermodynamic temperature \(T\)thermodynamically equivalent sphere in polymer chemistrythermoelectrometry thermogram thermogravimetry thermoluminescence thermolysis thermomagnetometry thermomechanical measurement thermometric thermometric enthalpy titration thermometric titration thermoparticulate analysis thermophile thermophotometry thermopile thermoplastic elastomer thermoptometry thermoreversible gel thermoreversible junction point thermoreversible network thermosetting polymer thermosonimetry thermosphere thermotropic mesophase thiazynes thick film thickness of diffusion layer in electrochemistrythickness of electrical double layer thickness of reaction layer in electrochemistrythin film thin-layer chromatography thio thioacetals thioaldehyde S-oxides thioaldehydes thioanhydrides thiocarboxylic acids thiocyanates thioethers thiohemiacetals thioketone S-oxides thioketones thiolates thiols thionylamines third body thixotropic gel thixotropy thiyl radicals threo threo structures threshold energy \(E_{0}\)threshold limit value through-bond electron transfer through-space electron transfer throughput rate throwing power TICT emission TICT state tie molecule in polymerstight ion pair time constant \(\tau_{\text{c}}\) of a detectortime of centrifugation \(t\) of centrifugationtime of deactivation in heterogeneous catalysistime of solidification, of thixotropic recoverytime-correlated single photon counting time-dependent density functional theory time-dependent stoichiometry time-independent stoichiometry time-of-flight mass spectrometer time-resolved anisotropy \(r(t)\)time-resolved fluorometry time-resolved microwave conductivity time-resolved spectroscopy time \(t\)titrant titration titration curve titration error titre tonne topical effect topochemical reaction topomerization topomers topotactic reaction topotactic transition torque \(T\)torquoselectivity torr torsion angle torsional braid analysis torsional stereoisomers torsional strain total absorption peak total chemiflux total consumption time \(t_{\text{tot}}\) in flame emission and absorption spectrometrytotal ion current total radiant power total retention volume \(V_{\text{R}}\),\(t_{\text{R}}\) in column chromatographytotal velocity of the analyte \(\nu_{\text{tot}}\) in capillary electrophoresistotally porous packing in chromatographytoxicity toxicodynamics toxicokinetics toxicology toxin toxinology trace element traceability tracer track (nuclear) track detector (nuclear) trajectory in reaction dynamicstrans trans conformation trans- in inorganic nomenclaturetrans-fused transannular strain transcription in biotechnologytransducer transduction in biotechnologytransfer transfer activity coefficient \(\mathit{\gamma}_{\text{t}}\)transfer in analysistransfer line transfer RNA transferability transferases transformation transformation in gene technologytransient (chemical) species transient crosslink transient junction point transient network transient phase (induction period) transient spectroscopy transient-stimulated emission pumping transit time \(t_{\text{ts}}\) in flame emission and absorption spectrometrytransition transition (dipole) moment transition coordinate transition element transition interval in titrimetric analysistransition layer transition polarization transition probability for absorption transition probability for spontaneous emission transition probability for stimulated emission transition species transition state transition state analogue transition state theory transition structure transition temperature (for liquid crystals) transition time in electroanalytical chemistrytransition wavenumber \(\tilde{\nu }\)translation in biotechnologytranslational spectroscopy transmission transmission coefficient transmission electron energy loss spectroscopy transmission electron microscopy transmission factor transmission high energy electron diffraction transmission in mass spectrometrytransmittance \(T\),\(\tau\)transoid conformation transport control transport in analysistransport interference in flame spectroscopytransport number \(t\)transposon transtactic polymer trapping travel time \(t_{\text{tv}}\) in flame emission and absorption spectrometrytreated solution in analytical chemistrytriads triangulo- triazanes triazenes triboluminescence trimethylenemethanes trioxides triple point triplet state triplet-triplet absorption triplet-triplet annihilation triplet-triplet energy transfer triplet-triplet transitions triprismo- tritactic polymer triterpenoids tritide tritio tritium triton trivial energy transfer trivial name tRNA Troe expression tropilidenes tropolones tropones tropopause troposphere tropyl radicals tropylium ions true coincidence in radiochemistrytrue value \(\tau\) in analysistub conformation tunable laser in spectrochemical analysisTung distribution of a macromolecular assemblytungsten-halogen lamp tunnelling turbidimetric titration turbidity \(\tau\) in light scatteringturnover frequency in catalysisturnstile rotation turntable reactor twist form twisted intramolecular charge transfer two-colour indicator two-dimensional chromatography two-photon excitation two-photon photochromism two-photon process two-site immunoradiometric assay θ temperature in polymersλ-transition
u ulosonic acids ultimate capacity in solvent extractionultrafiltrate ultrafiltration ultrasonic detector in gas chromatographyultraviolet umpire sample umpolung unactivated adsorption process uncertainty of measurement uniaxial pressing uniaxial sample unified atomic mass unit uniform corrosion uniform polymer uniformly labelled uniformly labelled tracer unimolecular unit in analytical chemistryunit cell unit of measurementunit system universal calibration in chromatographyuniversal detector in chromatographyunperturbed dimensions in polymersunreactive unresolved peak unstable unstable film unstable ion in mass spectrometryunsymmetrical films unzipping upconversion upfield uphill transport in membrane processesupper critical solution temperature upper limit of measurement in atmospheric trace component analysisupstream in membrane processesuptake ureides urethanes uronic acids uronium salts useful spectral range UV dose UV photoelectron spectroscopy UV stabilizer
vaccine vacuum phototube vacuum system in mass spectrometryvalence valence band valence isomer valence tautomerization valence transition value of a division of a precision balance scalevalue of a quantityvan der Waals adsorption van der Waals broadening van der Waals forces vaporization temperature \(T_{\text{vap}}\) in electrothermal atomizationvapour phase interference in analysisvariable pathlength cell in spectrochemical analysisvariable \(x\)variance \(V\),\(\sigma ^{2}\)variational transition state theory variegated star macromolecule Vavilov rule vector velocity in mass transportvelocity \(v\),\(c\)verdazyl radicals vertical ionization vertical transition Verwey transition vibrational redistribution vibrational relaxation vibrational term \(G\)vibrationally adiabatic transition-state theory vibronic coupling vibronic transition vidicon vinyl carbenes vinylic cations vinylic groups vinylidenes viologens virial coefficients virtual transition viscosity viscosity function \(\mathit{\Phi}\)viscosity number viscosity ratio viscous sintering visibility in atmospheric chemistryvisible volatilization volatilizer volt Volta potential difference voltage in electroanalysisvoltammetric constant volume content \(V_{\text{c}}/m_{\text{s}}\)volume flow rate \(q_{\text{v}}\)volume fraction \(\phi\)volume of activation \(\Delta ^{\ddagger}V\)volume of the stationary phase in chromatographyvolume rate volume reaction volume strain \(\theta\)volume viscosity volumetric flowrate in gas chromatographyvolumic vulcanization VUV ρ-value
Wagner number Walden inversion wall-coated open-tubular (WCOT) column in chromatographywash out in atmospheric chemistrywatt wave height (electrochemical) wavefunction \(\Psi \),\(\psi\),\(\varphi\)wavelength converter wavelength dispersion in X-ray emission spectroscopywavelength error in X-ray emission spectroscopywavelength-dispersive X-ray fluorescence analysis wavelength \(\lambda\)wavenumber \(\sigma\),\(\tilde{\nu }\)weak collision weathering weber wedge projection weight-distribution function weight \(G\)weighted mean Weller correlation Westcott cross-section wet bulb temperature wetting wetting tension Wheland intermediate Wiegner effect Wigner matrices Wigner rule Wilzbach labelling wind rose Wittig reagents wolfram lamp Wood horn Wood lamp Woodward–Hoffmann rules work hardening work of adhesion work of cohesion per unit area work of immersional wetting per unit area work of separation work softening work \(w\),\(W\)working electrode worm-like chain in polymers
x unit X-radiation X-ray escape peak X-ray fluorescence X-ray fluorescence analysis X-ray intensity X-ray level X-ray photoelectron spectroscopy X-ray satellite X-ray spectroscopy xanthates xanthene dyes xanthic acids xanthophylls xenobiotic xenon lamp xerogel XPS xylylenes ξ- (xi-)
YAG Yang photocyclization yard year yield \(Y\) in biotechnologyyield stress ylides ynamines ynols yocto yotta Young's modulus Yukawa–Tsuno equation
Z Z-value of a photochromic systemZaitsev rule Zeeman effect zepto zero differential overlap (ZDO) approximation zero field splitting zero point of a glass electrodezero point of scale of a balancezero–zero (0–0) absorption or emission zeta zetta zig-zag projection Zimm plot zone in chromatographyzone melting method of preconcentration Zucker–Hammett hypothesis zwitterionic compounds/zwitterions zwitterionic polymer zygote ζ-potential