电场作用下过冷水形核的分子动力学模拟

A MOLECULAR DYNAMICS SIMULATION ON THE NUCLEATION OF SUPERCOOLED WATER IN AN ELECTRIC FIELD

采用分子动力学模拟的方法研究了过冷水的结构和形核过程随电场强度变化的情况。对系统微观结构的分析显示在电场强度为0～10^(10)V/m范围内,处于200K的过冷水在5 ns时间内不足以发生形核,只有当电场强度增加到10^(11) V/m或者温度降低到100K时系统才能在5 ns内发生形核。模拟结果表明电场强度的改变对系统中水分子团簇的微观结构有明显影响,电场强度的增加能促进系统的短程有序性。

Molecular dynamics simulations are carried out to investigate the influence of an external electric field on the structure and nucleation of supercooled water. When the electric field strength is between 0 to 10^10 V/m and the system evolves within 5 ns, the structure analysis shows that the supercooled water at 200 K keeps in a liquid state. Only if the electric field is strengthened to 10^11 V/m or the temperature is lowered down 100 K, the water undergoes a nucleation. The results also show that the external electric field changes the microstructure of the water, and enhances the short-range ordering of the system.