氢键和堆积结构的对称自适应微扰理论相互作用能分解。

Symmetry-Adapted Perturbation-Theory Interaction-Energy Decomposition for Hydrogen-Bonded and Stacking Structures.

机构信息

Department of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland.

出版信息

J Chem Theory Comput. 2008 Jun;4(6):892-7. doi: 10.1021/ct800067m.

Abstract

This letter reports the computational ab initio studies on the stacked and hydrogen-bonded geometries of the uracil dimer and pyrimidine···p-benzoquinone complex with a special regard to the ratios of different interaction-energy terms calculated by means of the symmetry-adapted perturbation theory (SAPT). In the hydrogen-bonded systems the absolute value of the dispersion term constitutes approximately half of the absolute value of the total SAPT0 interaction energy, while in the stacking complexes the ratio of the dispersion to the total interaction energy is much larger, ca. 1.2-2.0. Our SAPT results are compared with the DFT-SAPT results published recently by the Hobza group (J. Chem. Phys. 2007, 127, 075104), and the role of the dispersion contribution in stacking and hydrogen-bonded arrangements is discussed. The methodological part of this letter presents the influence of counterpoise corrections in the optimization procedure on the geometries of the systems and the calculated SAPT contributions.

摘要

这封信报告了嘧啶二聚体和嘧啶···对苯醌复合物的堆积和氢键几何结构的从头算计算研究，特别关注通过对称自适应微扰理论 (SAPT) 计算的不同相互作用能项的比值。在氢键体系中，色散项的绝对值约占 SAPT0 总相互作用能的绝对值的一半，而在堆积复合物中，色散与总相互作用能的比值要大得多，约为 1.2-2.0。我们的 SAPT 结果与 Hobza 小组最近发表的 DFT-SAPT 结果进行了比较（J. Chem. Phys. 2007, 127, 075104），并讨论了色散贡献在堆积和氢键排列中的作用。这封信的方法部分介绍了在优化过程中对体系几何形状和计算的 SAPT 贡献的平衡校正的影响。