Zhang Zhigang, Duan Zhenhao
The Key Laboratory of Mineral Resources, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China.
J Chem Phys. 2005 Jun 1;122(21):214507. doi: 10.1063/1.1924700.
An optimized molecular potential model for carbon dioxide is presented in this paper. Utilizing the established techniques of molecular-dynamics and histogram reweighting grand canonical Monte Carlo simulations, this model is demonstrated to show excellent predictability for thermodynamic, transport, and liquid structural properties in a wide temperature-pressure range with remarkable accuracies. The average deviations of this new model from experimental data for the saturated liquid densities, vapor densities, vapor pressures, and heats of vaporization are around 0.1%, 2.3%, 0.7%, and 1.9%, respectively. The calculated critical point is almost pinpointed by the new model. The experimental radial distribution functions ranging from 240.0 to 473.0 K are well reproduced as compared to neutron-diffraction measurements. The predicted self-diffusion coefficients are in good agreement with the nuclear-magnetic-resonance measurements. The previously published potential models for CO2 are also systematically evaluated, and our proposed new model is found to be superior to the previous models in general.
本文提出了一种优化的二氧化碳分子势模型。利用分子动力学和直方图重加权巨正则蒙特卡罗模拟的既定技术，该模型在很宽的温度 - 压力范围内对热力学、输运和液体结构性质表现出出色的预测能力，具有显著的准确性。该新模型与饱和液体密度、蒸汽密度、蒸汽压和汽化热的实验数据的平均偏差分别约为0.1%、2.3%、0.7%和1.9%。新模型几乎精确地确定了计算出的临界点。与中子衍射测量结果相比，该模型很好地再现了240.0至473.0 K范围内的实验径向分布函数。预测的自扩散系数与核磁共振测量结果吻合良好。还对先前发表的二氧化碳势模型进行了系统评估，发现我们提出的新模型总体上优于先前的模型。
