超临界二氧化碳与共溶剂甲醇的分子动力学模拟

A Molecular Dynamics Simulation of Supercritical Carbon Dioxide with Methanol

采用分子动力学方法对不同压强和不同组分下的超临界二氧化碳加共溶剂体系的内能以及径向分布函数和自扩散系数等相关性质进行了模拟.模拟得到体系存在密度涨落现象,但此现象在高压下不明显,指出了体系以共溶剂聚集为主,并从径向分布函数和配位数方面进行了更详细的解释;解释了共溶剂分子的自扩散系数偏小现象正是由于聚集体的出现抑制了单个共溶剂分子的扩散.

The properties such as internal energy, radial distribution function and diffusion coefficient of the mixtures of supercritical carbon dioxide with methanol were simulated by using molecular dynamics simulations. Simulation system existence density fluctuations, but this phenomenon was not obvious under high pressure. It is pointed out that this system altogether by the co-solver primarily,and from the radial distribution function and coordination number for a more detailed explanation because of density fluctuations phenomenon the coefficient of co-solvent has been inhibited.