CH3SH与HOCl分子间氢键和卤键的结构与性质  

Structures and Properties of Halogen Bond and Hydrogen Bond Formed between CH_3SH and HOCl

作　　者：袁焜[1] 刘艳芝[1] 朱元成[1] 张继[2] 张俊彦[3] 

机构地区：[1]天水师范学院生命科学与化学学院,天水741001 [2]西北师范大学生命科学学院,兰州730000 [3]中国科学院兰州化学物理研究所,兰州730000

出　　处：《化学学报》2009年第6期499-506,共8页Acta Chimica Sinica

基　　金：甘肃省教育厅研究生导师科研基金(No.07-08-12);天水师范学院“青蓝”人才工程基金资助项目

摘　　要：在DFT-B3LYP及MP2/6-311++G**水平上分别求得CH3SH…HOCl氢键复合物和CH3SH…ClOH卤键复合物势能面上的稳定构型.频率分析表明,与单体HOCl相比,在两种复合物中,Cl(9)—O(7)和H(8)—O(7)键伸缩振动频率发生显著的红移.经MP2/6-311++G**水平计算的含基组重叠误差(BSSE)校正的气相中相互作用能分别为-19.23和-6.85 kJ·mol-1.自然键轨道理论(NBO)分析表明,在CH3SH…ClOH卤键复合物中,引起Cl(9)—O(7)键变长的因素包括2种电荷转移:(i)孤对电子LP[S(1)]1→σ*[Cl(9)—O(7)];(ii)孤对电子LP[S(1)]2→σ*[Cl(9)—O(7)],其中孤对电子LP[S(1)]2→σ*[Cl(9)—O(7)]转移占主要作用,总的结果是使σ*[Cl(10)—O(11)]的自然布居数增加,同时O(7)和Cl(9)原子s成分均增加的杂化重优具有与电荷转移作用相同的"拉长效应";在CH3SH…HOCl氢键复合物中也存在类似的电荷转移,但是O(7)原子的再杂化效应不同于前者.自然键共振理论(NRT)进行键序分析表明,在氢键复合物和卤键复合物中,H(8)—O(7)和Cl(9)—O(7)键的键序都减小.通过分子中原子理论(AIM)分析了复合物中氢键和卤键的电子密度拓扑性质.The optimized stable CH3SH…HOCl hydrogen bond and CH3SH…ClOH halogen bond complexes were located on the potential energy surface by means of DFT-B3LYP/6-311 ＋ ＋G^＊＊. The obvious red shifts of the H（8）--O（7） and Cl（9）--O（7） stretching vibrational frequencies in the two complexes were observed via frequency analysis. The halogen bond interaction energy of CH3SH…ClOH was --6.85 kJ·mol^-1, and the hydrogen bond interaction energy of CH3SH…HOCl was -19.23 kJ·mol^-1, which were calculated with basis set superposition error （BSSE） correction via a counterpoise procedure （CP） method. Natural bond orbital （NBO） theory analysis showed that two kinds of charge transfers exist in the CH3SH… ClOH halogen bond system： （i） lone pair LP[S（1）]^1→σ^＊[CI（9）-O（7）]; （ii） lone pair LP[S（1）]^2→σ^＊[Cl（9）- O（7）], and the natural population of the σ^＊[Cl（9）-O（7）] increased. Analogous charge transfers exist in the CH3SH…HOCI hydrogen bond complex. The bond order analysis with natural resonance theory （NRT） showed that bond order of Cl（9）--O（7） in the CH3SH…ClOH halogen bond complex and that of H（8）-- O（7） in the CH3S…HOCl hydrogen bond complex both decreased. The topological properties of the hydrogen bond and halogen bond structures were also investigated by the atoms-in-molecules （AIM） theory.

关 键 词：甲硫醇 次氯酸 氢键 卤键 自然键轨道理论 分子中原子理论 

分 类 号：O641.1[理学—物理化学]