Dimers of formic acid, acetic acid, formamide and pyrrole-2-carboxylic acid: an ab initio study
Dimers of formic acid, acetic acid, formamide and pyrrole-2-carboxylic acid: an ab initio study
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DOI：
10.1021/jp044072e
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发表时间：
2005-07-28
影响因子：
2.9
通讯作者：
Leszczynski, J
中科院分区：
文献类型：
--
作者：
Gora, RW;Grabowski, SJ;Leszczynski, J
研究了甲酸、乙酸和甲酰胺二聚体中的分子间氢键。此外，研究了吡咯-2-羧酸（PCA）二聚体的三种构型，分析了吡咯π电子系统如何影响双O-（HO）-O-连接的羧基。氢键在MP2/6-311++G（d，p），MP2/aug-cc-pVDZ和MP2/aug-cc-pVTZHMP 2/aug-cc-pVDZ水平上对体系进行了从头计算.利用Bader的“分子中的原子”理论，通过对临界点的分析，研究了氢键的性质。在这里应用的总相互作用能的分解表明，离域能量项是一个特别重要的吸引力的贡献，在这些系统中，更重要的是在系统形成homopolymer O-（HO）-O-的情况下。双氢键比那些通过杂环N-（HO）-O-连接的情况下。债券由于分析的系统可以被正式归类为共振辅助氢键（RAHB），它似乎是从离域相互作用能量项的主要贡献是这种相互作用的一个显着特点。
The intermolecular hydrogen bonds in dimers of formic acid, acetic acid, and formamide were investigated. Additionally, three configurations of the pyrrole-2-carboxylic acid (PCA) dimer were studied to analyze how the pyrrole pi-electron system influences the carboxylic groups connected by double O-(HO)-O-... hydrogen bonds. The ab initio calculations for the systems investigated were performed at MP2/6-311++G(d,p), MP2/aug-cc-pVDZ, and MP2/aug-cc-pVTZHMP2/aug-cc-pVDZ levels of theory. The "atoms in molecules" theory of Bader was used and the analysis of the critical points was performed to study the nature of hydrogen bonds. The decomposition of the total interaction energy applied here reveals that the delocalization energy term is a particularly important attractive contribution in these systems, more important in the case of systems forming homonuclear O-(HO)-O-... double hydrogen bonds than in the case of those connected through heteronuclear N-(HO)-O-... bonds. Because the systems analyzed may be formally classified as the resonance-assisted hydrogen bonds (RAHBs), it seems that the dominant contribution from the delocalization interaction energy term is a distinguished feature of such interactions.