Graduate Group in Applied Science, University of California Davis, Davis, California 95616, USA.
J Chem Phys. 2012 Jun 14;136(22):224107. doi: 10.1063/1.4727850.
We present a simplified implementation of the non-local van der Waals correlation functional introduced by Dion et al. [Phys. Rev. Lett. 92, 246401 (2004)] and reformulated by Román-Pérez et al. [Phys. Rev. Lett. 103, 096102 (2009)]. The proposed numerical approach removes the logarithmic singularity of the kernel function. Complete expressions of the self-consistent correlation potential and of the stress tensor are given. Combined with various choices of exchange functionals, five versions of van der Waals density functionals are implemented. Applications to the computation of the interaction energy of the benzene-water complex and to the computation of the equilibrium cell parameters of the benzene crystal are presented. As an example of crystal structure calculation involving a mixture of hydrogen bonding and dispersion interactions, we compute the equilibrium structure of two polymorphs of aspirin (2-acetoxybenzoic acid, C(9)H(8)O(4)) in the P2(1)/c monoclinic structure.
我们提出了 Dion 等人引入的非局域范德华相关泛函[Phys. Rev. Lett. 92, 246401 (2004)]的简化实现，并由 Román-Pérez 等人重新表述[Phys. Rev. Lett. 103, 096102 (2009)]。所提出的数值方法消除了核函数的对数奇点。给出了自洽相关势和应力张量的完整表达式。结合各种交换泛函的选择，实现了五种范德华密度泛函。应用于苯-水配合物相互作用能的计算和苯晶体平衡晶胞参数的计算。作为涉及氢键和色散相互作用混合物的晶体结构计算的一个例子，我们计算了两种阿司匹林（2-乙酰氧基苯甲酸，C(9)H(8)O(4)）多晶型物在 P2(1)/c 单斜晶系结构中的平衡结构。
