C_6H_6…H_2X(X=O、S、Se)复合物中XH…π键的从头计算法研究

Abinitio study of XH …π(X = O,S, and Se) interractions involving benzene

在MP2/6—311++G++基组水平下对苯水体系,苯硫化氢体系苯硒化氢体系可能存在的结构进行了全自由度能量梯度优化,找到了三个能量极小的π氢键结构BW,BS和BSe,它们的结合能分别是-10．25kJ/mol,-9．12kJ／mol,-9．83kJ／mol．通过电荷分析发现了电荷的流向从苯环流向给体的小分子．

The intermolecular of the the weak hydrogen-bonded complex of C6H6 - H2X（X = O, S, and Se） was optimized using the second-order MoUer-Plesset perturbation theory （MP2） at 6- 311 ＋ ＋ G^＊＊ lever. Three equilibrium structures （BW, BS, and BSe） was found. The binding energy of BW, BS, and BSe is - 10.25kJ/mol, - 9.12kJ/mol, - 9.83kJ/mol. The intermolecular electron charges transforming from the benzene to the H2X was found by NBO analysis.