The proton affinity (PA, E pa) of an anion or of a neutral atom or molecule is the negative of the enthalpy change in the reaction between the chemical species concerned and a proton in the gas phase: [1] + + + + +

质子亲和能（Proton Affinity）是化学物质结合一个孤立的质子所释放出的热量。

在质谱研究中，往往把化合物在气相状态下的碱性称为质子亲和势（proton affinity），又叫质子亲和力。 维基百科这样定义质子亲和势：The proton affinity (PA, E pa) of an anion or of a neutral atom or molecule is the negative of the enthalpy change in the reaction between above species and proton in the gas phase.理解起来，意思就是：阴离子/中性分子在气相条件下与质子反应后的焓变，是一个用能量. 导师曾经说过，质谱研究，就是气相化学的研究。 现在想起来，实在是 …

The ‘proton affinity’ and the related quantity ‘gas-phase basicity’ are defined as thermodynamic quantities that enable us to assign numeric values to the tendency of a molecule to accept a proton in the gas phase, or conversely, the tendency of a positive ion to donate a proton.

You may search for species based on proton affinity values in two ways: Specify a single value; the system will search for values within 5.0 kJ/mol (1.2 kcal/mol) of this value. Specify a range.

2020年9月2日 · 求助三个问题：一、质子亲和力PA(proton affinity)，是否可以理解为等于化学键异裂时的离解焓二、计算PA时需要焓相减，而很多文献并未提及温度，是默认了常温常压吗 ...,计算化学公社

2014年2月24日 · affinity is often, but unofficially, abbreviated as PA. PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1153 [Terms] [Paper] Citation: 'proton affinity' in IUPAC Compendium of Chemical Terminology, 3rd ed. International Union of Pure and Applied Chemistry; 2006.

In the following you will determine the proton affinity of water and its dependence on the level of theory employed to perform the calculation (i.e. basis set, electron correlation). Using your experience with water, you will then be able to estimate the proton affinity of methanol, CH 3 OH.

Formally the gas phase proton affinity (PA) of \(\ce{B}\) is defined as the negative of the enthalpy change for the its association with hydrogen: \[\ce{H^{+}(g) + B(g) <=> BH^{+}(g)} \label{eq1} \] where \(\Delta H_{rxn}\) is the Proton Affinity of \(\ce{B}\).

Abstract: Proton a nities for ethanol, formate, formic acid, methanol and methylamine calculated by ab initio Hartree-Fock and MP2 approaches, and various Density Functional Theory (DFT) methods are compared.