温度对二甲基亚砜水溶液的结构和热力学性质的影响  

Effect of Temperature on the Structural and Thermodynamic Properties of Aqueous Dimethyl Sulfoxide

作　　者：刘波[1] 黄世萍[1] 朱吉钦[2] 王鹏[3] 田辉平[3] 

机构地区：[1]北京化工大学纳米材料教育部重点实验室,北京100029 [2]北京化工大学化工资源有效利用国家重点实验室,北京100029 [3]中国石油化工股份有限公司石油化工科学研究院,北京100083

出　　处：《物理化学学报》2011年第2期289-294,共6页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(20876005;21076007);国家重点基础研究发展规划项目(973)(2010CB732301)资助~~

摘　　要：应用参考作用格位模型理论计算了二甲基亚砜(DMSO)摩尔分数为0.002时不同温度下溶液的微观结构和热力学性质.计算结果表明,DMSO加入到水中能够增强溶液的分子网络结构.温度升高,配位数减小,溶液中分子排布趋向无序.平均力势的波动增大表明分子间的诱导力表现为斥力.计算得到的各种热力学性质显示:温度升高,溶液的熵和溶剂化自由能增加,相互作用能和过剩化学位也增加,即高温下溶液越来越偏离理想溶液;空位形成能降低表明溶液分子结构在高温下更容易重组.The structural and thermodynamic properties of aqueous dimethyl sulfoxide（DMSO） at a mole fraction of 0.002 were investigated using referenced interaction site model theory at different temperatures.The results reveal that the water network structure is enhanced by the presence of DMSO.The increased fluctuation in the potential of mean force suggests that the water-induced force is repulsive.In addition,the increased entropy of solvation and free energy of solvation imply that the randomness of the solution increases with an increase in temperature.The increased interaction energy and excess chemical potential reveal that the solution deviates from an ideal solution.Furthermore,the increased cavity reorganization energy shows that the system structure reorganizes easily at high temperature.

关 键 词：参考作用格位模型 二甲基亚砜 微观结构 热力学性质 

分 类 号：O642[理学—物理化学]