圆柱形纳米孔道内受限溶液I2/Ar的分子动力学模拟研究

利用分子动力学模拟方法, 考察了受限于圆柱形纳米孔道内I2/Ar溶液的振动传能及扩散动力学. 计算得到了溶质振动弛豫时间T1、溶剂轴向扩散系数Dz随孔道半径变化的规律. 结果表明: T1随着孔道半径的增大而减小; 而Dz随着孔道半径的增大而增大; 与预期的一致, 随着孔道半径的增大, 孔道的限制作用逐渐减小, T1与Dz趋近于相应的非受限溶液体相值. 此外, 通过考察溶质、溶剂与孔道的相互作用, 在原子、分子层次上揭示了限制作用对传能与传质影响的机制.

Molecular Dynamics Simulations of I2/Ar Solution Confined in a Cylindrical Nanotube

Molecular dynamics simulations on vibrational energy transfer and diffusion of I2/Ar solution confined in a cylindrical nanotube have been performed. The solute vibrational energy relaxation time T1, as well as the solvent diffusion coefficient Dz along the nanotube was calculated as a function of radius of the nanotube. The results show that the T1 decreases as the radius increases, while the Dz takes the opposite trend. The confinement effect of the nanotube weakens quickly as the radius becomes larger, and as a result, both T1 and Dz tend towards the values of a bulk system as we expected. In addition, the mechanism of confinement effect on energy transfer and mass transport was explored at an atomic/molecular level by investigating the interactions among the nanotube, solute iodine and solvent argon.