N2O与HX(X=F,Cl,Br)分子间作用的电子密度拓扑研究  

Topological studies of electron density on the interaction between N_2O and HX (X=F,Cl,Br)

作　　者：苏玲[1] 孟令鹏[1] 郑世钧[1] 曾艳丽[1] 

机构地区：[1]河北师范大学化学与材料科学学院,计算量子化学研究所,河北石家庄050016

出　　处：《计算机与应用化学》2011年第2期156-160,共5页Computers and Applied Chemistry

基　　金：国家自然科学基金资助项目(20801017,20771033,20973053);河北省自然科学基金资助项目(B2008000138,B2008000141,B2010000371);河北省教育厅资助项目(2007123,2009137,2009138);河北师范大学博士基金资助项目(L2005B12,L2008B06)

摘　　要：运用量子化学微扰理论MP2方法和密度泛函B3LYP方法,采用6-311++G(d,p)基组,对N_2O分子与HX(X=F,Cl,Br)分子形成的氢键复合物进行构型优化和能量计算。利用电子密度拓扑分析方法对氢键复合物的拓扑性质进行了分析,探讨了分子间氢键作用的本质。研究结果表明,N_2O分子与HX(X=F,Cl,Br)分子间可形成O…H-X和N…H-X 2类氢键;形成氢键后,作为电子受体的HX(X=F,Cl,Br)分子中的H-X键键长增加振动频率减小;氢键作用能按照NNO…HF、NNO…HCl、NNO…HBr和ONN…HF、ONN…HCl、ONN…HBr的顺序递减;氢键形成过程中存在从电子给体到电子受体的电荷转移。复合物体系中的氢键作用介于共价键和离子键之间,并且以静电作用为主。The full geometry optimization and energy calculation of N_2O…HX（X= F,Cl,Br） hydrogen bonding system were carried out using MP2 and B3LYP methods at 6-311 ＋＋G（d,p） level.The topological properties of these hydrogen bonding complexes were investigated through topological analysis of electron density.The results indicated that there were two sorts of hydrogen bonds which existed in N_2O-HX（X= F,Cl,Br） hydrogen bonding system.One was O…H-X,and the other was N…H-X.After the formation of the hydrogen bond,the H-X bond in the HX（X= F,Cl,Br） molecule was elongated and the vibrational frequencies of this bond was decreased.The energy of the hydrogen bond followed this pattern： NNO…HFNNO…HClNNO…HBr and ONN…HFONN…HClONN…HBr.Besides,charge transfer from donor atoms to acceptor atoms was observed during the hydrogen bonding formation process.The character of this hydrogen bond was between covalent and ionic interactions,with static interaction being dominant.

关 键 词：氢键复合物 弱相互作用 电子密度拓扑分析 分子中的原子理论 

分 类 号：O641[理学—物理化学]