氯化钙甲醇溶液中离子溶剂化作用的理论研究  

A theoretical study on ion solvation of CaCl_2/methanol solution

作　　者：吴晓静[1] 代云[1] 

机构地区：[1]合肥工业大学化工学院,合肥230009

出　　处：《中国科学：化学》2011年第10期1597-1603,共7页SCIENTIA SINICA Chimica

摘　　要：利用红外光谱研究不同温度下CaCl2/甲醇溶液体系的溶剂化作用,结果表明在溶液中CaCl2以离子形式与甲醇发生溶剂化作用,且溶剂化数随温度升高而降低.通过密度泛函理论(DFT)在B3LYP/6-31G**水平下对CaCl2/甲醇溶液中可能存在的配位构型进行结构优化及热力学性质的计算,说明了在CaCl2/甲醇溶液中各种配位构型存在的可能性,得出温度升高热力学数据的变化规律,解释了溶剂化数随温度升高而降低的趋势.进一步对各种可能配位构型的红外吸收频率进行计算并与实验结果进行比较,推断在CaCl2/甲醇溶液中主要存在的配位构型为[CaCl(CH3OH)n]+和[Cl(CH3OH)n]-.The solvation of CaCl2/methanol solutions has been investigated by infrared spectroscope in different temperatures.It has been found that CaCl2 would coordinate with methanol in the form of ions in the solution,and the solvation number would decrease with increasing temperature.Moreover the optimized structures and thermodynamic properties of possible complexes in CaCl2/methanol solution have been calculated by DFT at the level of B3LYP/6-31G＊＊,which explained the tendency that solvation number reduced with increasing temperature in theory.In addition the infrared absorption frequency of possible complexes also has been calculated.Comparing with experimental results,it could be concluded that the main complexes forms are [CaCl（CH3OH）n]＋ and [Cl（CH3OH）n]-in CaCl2/methanol solution.

关 键 词：离子溶剂化 甲醇 密度泛函理论红外光谱 

分 类 号：O646[理学—物理化学]