Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA.
J Chem Phys. 2018 Jun 28;148(24):241736. doi: 10.1063/1.5025226.
A meta-generalized gradient approximation, range-separated double hybrid (DH) density functional with VV10 non-local correlation is presented. The final 14-parameter functional form is determined by screening trillions of candidate fits through a combination of best subset selection, forward stepwise selection, and random sample consensus (RANSAC) outlier detection. The MGCDB84 database of 4986 data points is employed in this work, containing a training set of 870 data points, a validation set of 2964 data points, and a test set of 1152 data points. Following an xDH approach, orbitals from the ωB97M-V density functional are used to compute the second-order perturbation theory correction. The resulting functional, ωB97M(2), is benchmarked against a variety of leading double hybrid density functionals, including B2PLYP-D3(BJ), B2GPPLYP-D3(BJ), ωB97X-2(TQZ), XYG3, PTPSS-D3(0), XYGJ-OS, DSD-PBEP86-D3(BJ), and DSD-PBEPBE-D3(BJ). Encouragingly, the overall performance of ωB97M(2) on nearly 5000 data points clearly surpasses that of all of the tested density functionals. As a Rung 5 density functional, ωB97M(2) completes our family of combinatorially optimized functionals, complementing B97M-V on Rung 3, and ωB97X-V and ωB97M-V on Rung 4. The results suggest that ωB97M(2) has the potential to serve as a powerful predictive tool for accurate and efficient electronic structure calculations of main-group chemistry.
提出了一种元广义梯度逼近、带 VV10 非局部相关的范围分离双杂交 (DH) 密度泛函。最终的 14 参数函数形式是通过结合最佳子集选择、前向逐步选择和随机样本共识 (RANSAC) 异常值检测，从数万亿个候选拟合中筛选出来的。该工作采用了 MGCDB84 数据库中的 4986 个数据点，其中包含 870 个数据点的训练集、2964 个数据点的验证集和 1152 个数据点的测试集。采用 xDH 方法，ωB97M-V 密度泛函的轨道用于计算二阶微扰理论校正。得到的功能，ωB97M(2)，与各种领先的双杂交密度泛函进行了基准测试，包括 B2PLYP-D3(BJ)、B2GPPLYP-D3(BJ)、ωB97X-2(TQZ)、XYG3、PTPSS-D3(0)、XYGJ-OS、DSD-PBEP86-D3(BJ)和 DSD-PBEPBE-D3(BJ)。令人鼓舞的是，ωB97M(2)在近 5000 个数据点上的整体性能明显优于所有测试的密度泛函。作为一个第五级密度泛函，ωB97M(2)完成了我们的组合优化泛函家族，补充了第三级的 B97M-V，以及第四级的 ωB97X-V 和 ωB97M-V。结果表明，ωB97M(2)有可能成为一种强大的预测工具，用于准确和高效地计算主族化学的电子结构。
