bond-dissociation enthalpy

symbols: ${\rm{D}}H^{\circ}$, $\Delta_{\rm{diss}} H^{\circ}$, unit: $\pu{kJ mol-1}$
https://doi.org/10.1351/goldbook.08146
Standard molar enthalpy required to break a given bond of some specific molecular entity by homolysis.

Example: For \(\ce{CH4 -> CH3. + H.}\), the bond-dissociation enthalpy is symbolized as \({\rm{D}}H^{\circ}(\ce{CH3-H})\).

Note: Although \({\rm{D}}H^{\circ}\) is commonly used, \(\Delta_{\rm{diss}} H^{\circ}\) is more consistent with the notation for other thermodynamic quantities.

Source:
PAC, 2022, 94, 353. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 2021)) on page 372 [Terms] [Paper]