NaF-NaCl熔融系统的分子动力学模拟

Molecular_dynamics Simulation Study of Molten NaF-NaCl Mixtures

用分子动力学模拟方法,分别采用带电刚性球势、Fumi＿Tosi势和改进的Fumi＿Tosi势研究了熔融NaF＿NaCl系统的混合效应。模拟结果表明:采用带电刚性球势、Fumi＿Tosi势得到的混杂焓只在富Cl-端与实验值定性一致,而改进的Fumi＿Tosi势的混杂焓在两端都与实验值定性一致,即在NaF一端为弱吸热,而在NaCl一端为弱放热。分析表明:前者低估了极化对混杂焓的贡献。

The mixed effect of molten NaF_NaCl systems is studied over the full concentration range at T=1273K by molecular_dynamics simulation.Thermodynamic properties are calculated with the charged hard_sphere potential,the Fumi_Tosi potential and the improved Fumi_Tosi potential and compared with experiments,respectively.The results of the simulations suggest that the excess mixed enthalpy with the charged hard_sphere potential and the Fumi_Tosi potential are only qualitative consistent with the experiments' results at high chlorine concentration,while those with the improved Fumi_Tosi potential are qualitative consistent with the experiments' results at both high chlorine and high fluorine concentration.The analysis suggests that the former two potentials underestimate the polarization contributions.