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Updated: May 9, 2026

Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Protophilicity index and protofelicity equalization principle: new measures of Brønsted-Lowry-Lewis acid-base
Francisco Méndez1, Julio A Alonso, Arlette Richaud
1Departamento de Química, División de Ciencias Básicas e Ingeniería, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-534, México, DF, 09340, Mexico. fm@xanum.uam.mx
Abstract:
The simultaneous contributions of proton and electron transfer to the Brønsted-Lowry and Lewis acid-base properties of a set of p-substituted phenols are reported in this work. As a result of the analysis, a novel protophilicity index considered as the second-order energy change of a Brønsted-Lowry base as it is saturated with protons, a combined Brønsted-Lowry-Lewis acidity index (with a corresponding basicity index), and a protofelicity equalization principle (a parallel of the electronegativity equalization principle) are presented.
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