文献类型：会议论文

英文题名：Cation sitting in aromatic cages: Ab initio computational studies on tetramethylammonium-(benzene)n (n=3-4) complexes

作者：Cheng, Jiagao[1,2,3]; Gong, Zhen[2]; Zhu, Weiliang[1,2]; Tang, Yun[3]; Li, Weihua[3]; Li, Zhong[3]; Jiang, Hualiang[2,3]

机构：[1] School of Science, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China; [2] Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China; [3] School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China

语种：英文

外文关键词：Binding energy - Bond strength (chemical) - Positive ions - Quantum chemistry

摘要：Quantum chemistry study was performed on interaction between tetramethylammonium (TMA) and aromatic cages by means of the MP2 method to show how TMA sits in an aromatic cage that is composed of benzenes. The MP2 calculations on TMA-(benzene)n complexes demonstrate that the more the benzene molecules in the aromatic cage, the stronger the binding strength between the cage and TMA. In details, the structure of TMA-(benzene)n (n = 1-4) complexes can be easily constructed by superimposing n TMA-benzene complexes via TMA, and the binding energies of the TMA-(benzene)n complexes are the sum of the n corresponding TMA-benzene systems. For instance, the distances between the N of TMA and the plane of the benzene ring are 4.238, 4.252, 4.264 ,and 4.276 ?, respectively, for TMA-(benzene)n (n = 1-4) complexes, and the BSSE corrected binding energies at MP2/6-311++G** level are -8.8, -17.3, -25.8 and -34.3 kcal/mol, respectively, for TMA-(benzene)n (n = 1-4) complexes. Thus, this study provides us useful information on how a cation interacts with an aromatic cage in terms of complex geometry and binding strength. Copyright ? 2007 John Wiley & Sons, Ltd.