Molecular dynamics simulation study on condensation coefficients of different potential models for water

Equilibrium molecular dynamics (EMD) simulations were carried out in this study to investigate the condensation processes of water. By using characteristic time method, the condensation coefficients for five different types of potential models (SPC, SPCE, TIP3P, TIP4P and TIP5P) were obtained at different temperatures. The results show that the condensation coefficient decreases with the increase of the temperature. When the temperature is higher than 400 K, at the same temperature the descending order of the condensation coefficients for different models is SPCE, TIP4P, TIP3P, SPC and TIP5P, while the difference between the coefficients of TIP4P and TIP3P is tiny. However, when the temperature is lower than 400 K, there are no remarkable differences between the coefficients of the five models at the same temperature. Moreover, the TIP5P can not form the liquid-vapor coexistent region at high temperatures (approximately higher than 520 K), thus the statistic determination for the condensation coefficients fails.