原子能科学技术2026，Vol.60Issue(4)：769-778,10.DOI:10.7538/yzk.2025.youxian.0712
LiCl-KCl-UCl3熔盐体系的极化力场发展及应用
Development and Applications of Polarizable Force Fields for LiCl-KCl-UCl3 Molten Salt System
摘要
Abstract
The LiCl-KCl-UCl3 molten salt systems play a crucial role in the electrorefining process of spent nuclear fuel pyro-processing,where their microstructure and physicochemical properties directly affect the efficiency of uranium recovery.Experimental studies on actinide-containing molten salts are often challenging due to the unavoidable extreme conditions such as high temperatures,corrosiveness and strong radioactivity.Molecular dynamics(MD)simulations serve as a powerful alternative tool for investigating the microscopic structure and thermophysical properties of such systems.In particular,classical MD based on the polarizable ion model(PIM)potential has been widely used to relatively accurately describe the microstructure,thermodynamics,and transport properties of high-temperature molten salts.In this work,a new set of PIM force field parameters were developed via a force-matching approach,incorporating the polarization effects of U3+,K+,and Cl-ions.Using this force field,MD simulations were performed to systematically study the microstructure,coordination chemistry,ionic correlations,and dynamic properties of the LiCl-KCl-UCl3 system.The results demonstrate that the newly developed force field fairly accurately reproduces U-Cl coordination structures,bridging coordination modes,and molten salt density,agreeing well with experimental data and ab initio molecular dynamics(AIMD)simulations.The MD simulation results reveal that the U-Cl coordination shell exhibits relatively high stability,with the coordination number of uranium decreasing as temperature increases.Moreover,KCl acts as a"spacer salt",leading to KCl-separated correlations between complexes and networks at intermediate length scales.Additionally,the self-diffusion coefficients of the ionic species and the viscosity of the melt were computed,both of which follow Arrhenius-type behavior.This study provides a computational simulation framework for understanding the structures and properties of actinide molten salt systems.The developed simulation method offers atomic-scale insights into the microstructural and dynamic behavior of uranium-containing melts,providing theoretical guidance for the separation and extraction of actinide elements.关键词
锕系元素/高温熔盐/分子动力学/极化力场/配位化学Key words
actinides/high-temperature molten salt/molecular dynamics/polarizable force field/co-ordination chemistry分类
能源科技引用本文复制引用
刘建标,宋俊杰,鲁俊波,叶国安,李隽..LiCl-KCl-UCl3熔盐体系的极化力场发展及应用[J].原子能科学技术,2026,60(4):769-778,10.基金项目
国家自然科学基金(22033005,21601110,22403095) （22033005,21601110,22403095）
中国科学院赣江创新研究院稀土基础科学研究中心启动基金 （）
