Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Campus Hubland Nord, Emil-Fischer-Strasse 42, D-97074 Würzburg, Germany.
J Phys Chem B. 2013 Sep 5;117(35):10093-102. doi: 10.1021/jp403578r. Epub 2013 Aug 21.
Symmetry-adapted perturbation theory (SAPT) is used to decompose the total intermolecular interaction energy between the ammonium cation and a benzene molecule into four physically motivated individual contributions: electrostatics, exchange, dispersion, and induction. Based on this rigorous decomposition, it is shown unambiguously that both the electrostatic and the induction energy components contribute almost equally to the attractive forces stabilizing the dimer with a nonnegligible contribution coming from the dispersion term. A polarizable potential model for the interaction of ammonium cation with benzene is parametrized by fitting these four energy components separately using the functional forms of the AMOEBA force field augmented with the missing charge penetration energy term calculated as a sum over pairwise electrostatic energies between spherical atoms. It is shown that the proposed model is able to produce accurate intermolecular interaction energies as compared to ab initio results, thus avoiding error compensation to a large extent.
对称自适应微扰理论 (SAPT) 被用于将铵阳离子与苯分子之间的总分子间相互作用能分解为四个具有物理意义的单独贡献：静电、交换、色散和诱导。基于这种严格的分解，可以明确地表明静电能和诱导能分量几乎对稳定二聚体的吸引力做出了相等的贡献，色散项也有不可忽视的贡献。通过分别使用 AMOEBA 力场的函数形式以及通过球形原子之间的静电能求和计算的缺失电荷穿透能项来拟合这四个能量分量，为铵阳离子与苯的相互作用参数化了一个可极化的势能模型。结果表明，与从头算结果相比，所提出的模型能够产生准确的分子间相互作用能，从而在很大程度上避免了误差补偿。
