Gale Julian D, LeBlanc Luc M, Spackman Peter R, Silvestri Alessandro, Raiteri Paolo
Curtin Institute for Computation, School of Molecular and Life Sciences, Curtin University, PO Box U1987, Perth, Western Australia 6845, Australia.
J Chem Theory Comput. 2021 Dec 14;17(12):7827-7849. doi: 10.1021/acs.jctc.1c00832. Epub 2021 Nov 4.
In this study, the adaption of the recently published molecular GFN-FF for periodic boundary conditions (pGFN-FF) is described through the use of neighbor lists combined with appropriate charge sums to handle any dimensionality from 1D polymers to 2D surfaces and 3D solids. Numerical integration over the Brillouin zone for the calculation of π bond orders of periodic fragments is also included. Aside from adapting the GFN-FF method to handle periodicity, improvements to the method are proposed in regard to the calculation of topological charges through the inclusion of a screened Coulomb term that leads to more physical charges and avoids a number of pathological cases. Short-range damping of three-body dispersion is also included to avoid collapse of some structures. Analytic second derivatives are also formulated with respect to both Cartesian and strain variables, including prescreening of terms to accelerate the dispersion/coordination number contribution to the Hessian. The modified pGFN-FF scheme is then applied to a wide range of different materials in order to examine how well this universal model performs.
在本研究中，通过使用邻居列表并结合适当的电荷总和来描述最近发表的用于周期性边界条件的分子GFN-FF（pGFN-FF）的改编，以处理从一维聚合物到二维表面和三维固体的任何维度。还包括在布里渊区上进行数值积分以计算周期性片段的π键级。除了改编GFN-FF方法以处理周期性外，还通过包含屏蔽库仑项对拓扑电荷的计算提出了方法改进，这会产生更符合物理的电荷并避免一些病态情况。还包括三体色散的短程阻尼以避免某些结构的坍塌。还针对笛卡尔变量和应变变量制定了解析二阶导数，包括对项进行预筛选以加速色散/配位数对海森矩阵的贡献。然后将修改后的pGFN-FF方案应用于广泛的不同材料，以检验这个通用模型的性能如何。
