Predicting vapor liquid equilibria using density functional theory: A case study of argon
Predicting vapor liquid equilibria using density functional theory: A case study of argon
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DOI：
10.1063/1.5025726
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发表时间：
2018-06-14
影响因子：
4.4
通讯作者：
Rai, Neeraj
中科院分区：
文献类型：
--
作者：
Goel, Himanshu;Ling, Sanliang;Rai, Neeraj
使用第一原理方法预测由弱范德华 (vdW) 相互作用控制的分子的气液平衡 (VLE) 是一项重大挑战。由于后 Hartree-Fock 波函数理论与系统尺寸/基函数的标度较差，因此 Kohn-Sham 密度泛函理论 (DFT) 对于具有大量分子的系统是首选。然而，传统的 DFT 无法充分解释中长期相关性，而这对于建模 vdW 相互作用是必需的。 DFT 的最新发展（例如色散校正模型和非局部范德华函数）试图解决这一弱点，并取得了不同程度的成功。在这项工作中，我们通过第一原理蒙特卡罗模拟确定临界和结构特性，预测了氩气的 VLE，并评估了几种密度泛函和二阶 Moller-Plesset 微扰理论 (MP2) 的性能。 PBE-D3、BLYP-D3 和 rVV10 泛函用于计算气液共存曲线，而 PBE0-D3、M06-2X-D3 和 MP2 用于计算单态点的液体密度。 VLE 泛函的 PBE-D3 性能优于其他泛函（BLYP-D3 和 rVV10）。在 T = 85 K 和 P = 1 bar 时，MP2 在液相中第一溶剂化壳的密度和结构特征方面表现良好。由 AIP 出版社出版。
Predicting vapor liquid equilibria (VLE) of molecules governed by weak van derWaals (vdW) interactions using the first principles approach is a significant challenge. Due to the poor scaling of the post Hartree-Fock wave function theory with system size/basis functions, the Kohn-Sham density functional theory (DFT) is preferred for systems with a large number of molecules. However, traditional DFT cannot adequately account for medium to long range correlations which are necessary for modeling vdW interactions. Recent developments in DFT such as dispersion corrected models and nonlocal van der Waals functionals have attempted to address this weakness with a varying degree of success. In this work, we predict the VLE of argon and assess the performance of several density functionals and the second order Moller-Plesset perturbation theory (MP2) by determining critical and structural properties via first principles Monte Carlo simulations. PBE-D3, BLYP-D3, and rVV10 functionals were used to compute vapor liquid coexistence curves, while PBE0-D3, M06-2X-D3, and MP2 were used for computing liquid density at a single state point. The performance of the PBE-D3 functional for VLE is superior to other functionals (BLYP-D3 and rVV10). At T = 85 K and P = 1 bar, MP2 performs well for the density and structural features of the first solvation shell in the liquid phase. Published by AIP Publishing.