Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark.
Instituto de Física da Universidade de São Paulo, Rua do Matão 1371, 05508-090 São Paulo, SP, Brazil.
Phys Chem Chem Phys. 2021 Sep 22;23(36):20340-20351. doi: 10.1039/d1cp02315b.
The formal potentials for the reversible one-electron oxidation of ,,',' tetrasubstituted -phenylenediamines in acetonitrile have been applied as a test set for benchmarking computational methods for a series of compounds with only small structural differences. The aim of the study is to propose a simple method for calculating the standard oxidation potentials, and therefore, the protocol is progressively developed by adding more terms in the energy expression. In addition, the effect of including implicit solvation models (IEFPCM, CPCM, and SMD), larger basis sets, and correlation methods are investigated. The oxidation potentials calculated using the G3MP2B3 approach with IEFPCM resulted in the best fit ( = 0.9624), but the slope of the correlation line, 0.74, is far from the optimal value, 1.00. B3LYP/6-311++G(d,p) and TPSSh/6-311++G(2d,p) yielded only slightly less consistent data ( = 0.9388 and = 0.9425), but with much better slopes, 1.00 and 0.94, respectively. We conclude that it is important to investigate the basis set size and treatment of electron correlation when calculating oxidation potentials for ,,',' tetrasubstituted -phenylenediamines.
在乙腈中， ，'，四取代 - 苯二胺可逆单电子氧化的形式电势已被用作基准测试的测试集，用于比较具有微小结构差异的一系列化合物的计算方法。该研究的目的是提出一种计算标准氧化电势的简单方法，因此，该方案通过在能量表达式中添加更多项来逐步发展。此外，还研究了包括隐式溶剂化模型（IEFPCM、CPCM 和 SMD）、更大的基组和相关方法的影响。使用 G3MP2B3 方法和 IEFPCM 计算的氧化电势得到了最佳拟合（ = 0.9624），但相关线的斜率为 0.74，远低于最佳值 1.00。B3LYP/6-311++G(d,p) 和 TPSSh/6-311++G(2d,p) 仅产生略低一致性的数据（ = 0.9388 和 = 0.9425），但斜率更好，分别为 1.00 和 0.94。我们得出结论，在计算 ，'，四取代 - 苯二胺的氧化电势时，研究基组大小和电子相关处理非常重要。
