水及其表面活性剂体系汽—液界面行为的分子动力学模拟

Molecular Dynamics Simulation of Vapor-liquid Interface Behavior for Water and Surfactant Aqueous Solution Systems

采用分子动力学模拟技术,对水及其表面活性剂体系的汽—液界面行为进行了研究。模拟结果表明,随着温度的升高,纯水体系液相主体密度降低,气—液界面厚度增大,界面张力逐渐减小;水—十二烷基硫酸钠体系与纯水体系相比,汽—液界面厚度明显增大,汽—液界面张力明显减小,其随温度的变化规律和纯水体系一致。

The vapor - liquid interface behavior of water and surfactant aqueous solution systems is inves- tigated by molecular dynamics simulation. The simulation results indicate that the vapor - liquid interface thickness of water increases as temperature increases, but the density of liquid bulk and the interface tension show opposite tendency. It is also found that the vapor -liquid interface thickness increases obviously and the interface tension reduces significantly compared to the water system, while its variation with temperature is consistent with water system.