Gould Tim, Johnson Erin R, Tawfik Sherif Abdulkader
Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia.
Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4R2, Canada.
Beilstein J Org Chem. 2018 May 23;14:1181-1191. doi: 10.3762/bjoc.14.99. eCollection 2018.
Modern approaches to modelling dispersion forces are becoming increasingly accurate, and can predict accurate binding distances and energies. However, it is possible that these successes reflect a fortuitous cancellation of errors at equilibrium. Thus, in this work we investigate whether a selection of modern dispersion methods agree with benchmark calculations across several potential-energy curves of the benzene dimer to determine if they are capable of describing forces and energies outside equilibrium. We find the exchange-hole dipole moment (XDM) model describes most cases with the highest overall agreement with reference data for energies and forces, with many-body dispersion (MBD) and its fractionally ionic (FI) variant performing essentially as well. Popular approaches, such as Grimme-D and van der Waals density functional approximations (vdW-DFAs) underperform on our tests. The meta-GGA M06-L is surprisingly good for a method without explicit dispersion corrections. Some problems with SCAN+rVV10 are uncovered and briefly discussed.
现代模拟色散力的方法越来越精确，能够预测准确的结合距离和能量。然而，这些成功可能反映了在平衡状态下误差的偶然抵消。因此，在这项工作中，我们研究了几种现代色散方法在苯二聚体的几条势能曲线上是否与基准计算结果一致，以确定它们是否能够描述平衡之外的力和能量。我们发现，交换空穴偶极矩（XDM）模型在大多数情况下与能量和力的参考数据总体一致性最高，多体色散（MBD）及其分数离子（FI）变体的表现也基本相同。在我们的测试中，流行的方法，如Grimme-D和范德华密度泛函近似（vdW-DFAs）表现不佳。元广义梯度近似（meta-GGA）的M06-L对于一种没有明确色散校正的方法来说出奇地好。我们发现了SCAN+rVV10的一些问题并进行了简要讨论。
