The negative of the Gibbs energy (ΔGr°) change associated with the reaction: in the gas phase.
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Also called absolute or intrinsic basicity.
See also: proton affinity
Source:
PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1116 (https://doi.org/10.1351/pac199466051077)