https://doi.org/10.1351/goldbook.P04907
The negative of the
enthalpy
change in the gas phase reaction (real or hypothetical) between a
proton
(more appropriately
hydron
) and the
chemical species
concerned, usually an electrically neutral species to give the
conjugate acid
of that species.
Proton
affinity is often, but unofficially, abbreviated as PA.
See also:
gas-phase basicity
Source:
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1153 [Terms] [Paper]