基于密度泛函理论的KF-NaF-AlF3低温电解质体系势参数拟合及分子动力学模拟  

Potential parameter fitting and molecular dynamics simulation of KF-NaF-AlF3 low temperature electrolyte system based on density functional theory

作　　者：王景坤 国辉 张红亮 李劼[1,3] WANG Jingkun;GUO Hui;ZHANG Hongliang;LI Jie(School of Metallurgy and Environment,Central South University,Changsha 410083,China;China Hongqiao Group Limited,Zouping 256200,China;National Engineering Laboratory for High Efficiency Recovery of Refractory Nonferrous Metals,Central South University,Changsha 410083,China)

机构地区：[1]中南大学冶金与环境学院,湖南长沙410083 [2]中国宏桥集团有限公司,山东邹平256200 [3]中南大学难冶有色金属资源高效利用国家工程实验室,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2020年第12期3300-3308,共9页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金面上项目(51974373,51674300,51874365,61751312);湖南省自然科学基金面上项目(2018JJ2521)。

摘　　要：基于密度泛函理论构建KF-NaF-AlF3熔盐体系的Buckingham势参数,基于所构建的势参数对KF-NaF-AlF3熔盐体系进行分子动力学模拟。研究结果表明:熔盐中主要的阴离子构型为F^-,[AlF4]^-,[AlF5]^2-和[AlF6]^3-;由于桥氟离子的存在,熔盐中形成了更复杂的Al-F-Al络合离子构型,如[Al2F8]^2-,[Al3F10]^-,[Al4F14]^2-,[Al4F15]^3-和[Al4F16]^4-等,这些复杂阴离子的存在可能会进一步降低KF-NaF-AlF3熔盐的输运性能。Buckingham potential parameters of KF-NaF-AlF3molten salt system were constructed based on density functional theory.Molecular dynamics simulation of KF-NaF-AlF3molten salt system was carried out based on the constructed potential parameters.The results show that the main anion configurations in the molten salt are F^-,[AlF4]^-,[AlF5]^2-and[AlF6]^3-.Due to the presence of bridge F ions,more complex Al-F-Al complex ion configurations are formed in the molten salt,such as[Al2F8]^2-,[Al3F10]^-,[Al4F14]^2-,[Al4F15]^3-and[Al4F16]^4-,etc.The existence of these complex anions may further reduce the transport performance of the molten salt KF-NaF-AlF3.

关 键 词：势参数拟合 KF-NaF-AlF3 分子动力学模拟 离子结构 

分 类 号：TF821[冶金工程—有色金属冶金]