Cs^+水合结构的密度泛函理论计算研究  

Hydration Structure of Cs+with Density Function Theory

作　　者：张文倩 房春晖[1,2] 朱发岩 刘红艳[1,2] 李武 王广国[1,2,3] 周永全 ZHANG Wen-qian;FANG Chun-hui;ZHU Fa-yan;LIU Hong-yan;LI Wu;WANG Guang-guo;ZHOU Yong-quan(Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources,Qinghai Institute of Salt Lakes,Chinese Academy of Sciences,Xining ,810008,China;Key Laboratory of Salt Lake Resources Chemistry of Qinghai Province ,Xining,810008,China;University of Chinese Academy of Sciences,Beijing,10049,China)

机构地区：[1]中国科学院青海盐湖研究所,中国科学院盐湖资源综合高效利用重点实验室,青海西宁810008 [2]青海省盐湖资源化学重点实验室,青海西宁810008 [3]中国科学院大学,北京100049

出　　处：《盐湖研究》2018年第4期51-63,共13页Journal of Salt Lake Research

基　　金：国家自然科学基金面上项目(21573268);盐湖联合基金项目(U1607106);青海省自然科学基金青年项目(2015-ZJ-945Q)

摘　　要：基于密度泛函理论在ωB97XD/gen def2-tzvp基组水平上对[Cs(H_2O)_n]^+(n=1～15)水合团簇结构的振动光谱进行了研究。研究表明,随着水分子数的增加,在气相和液相中,八配位的Cs^+水合团簇是最稳定的;随着水分子数的增加,Cs-O键长增大,Cs^+上的电荷密度减小。当水分子数大于11时,Cs-O键长和Cs^+上的电荷密度变化很小。O(H_2O)-O(H_2O)距离、∠O(H_2O)-Cs-O(H_2O)°统计结果表明,15个水分子足以形成Cs^+的近似饱和水合层。此外,红外光谱显示[Cs(H_2O)_n]^+水合团簇中O-H伸缩振动随着水分子数的增加而发生变化,由此可以作为鉴别水合层位置的一种参考方法。The density functional theory with ωB97 XD/gen def2-tzvp was used to study the hydration structure of[Cs(H2O)n]+(n=1-15) clusters. The results show that with increasing of the water molecules,eight-coordinated water molecules for Cs+ clusters is the most stable structure in gas or aqueous phase. The distances of Cs-O increases while the charge density of Cs+ decline with increasing of water molecules. When there are more than eleven water molecules around Cs+,the distance of Cs-O and Cs+ charge density changes a little.The statistical results of the average distance O-O,the∠O-Cs-O° of [Cs(H2O)n]+(n=1-15) clusters illustrates that fifteen water molecules are enough to form an approximated complete hydration shell for Cs+. Furthermore,IR spectra of [Cs(H2O)n]+(n=1-15) clusters presents that O-H stretching vibration changing with increasing water molecules,thus it can be a reference to identify the position(hydration shell) of water molecules in hydration clusters.

关 键 词：[Cs(H2O)n]^+(n=1~15)水合团簇 配位数 水合离子 红外光谱 

分 类 号：O611.2[理学—无机化学]