A novel DFT-D method,B972-PFD,has been found by combining the B972 hybrid density functional with the empirical dispersion correction based on the spherical atom model (SAM).The performance of the B972-PFD method is assessed on the S66,S66x8,and S22 standard data sets,atmospheric hydrogen-bonded clusters,the Adenine-Thymine Π…Π stacked,Watson-Crick hydrogen-bonded complexes,and the methane to (H2O)20 water cluster.The benchmark results of the S66 test set show that B972-PFD and three recently developed density functionals,ωB97X-V,B97M-V,and ωB97M-V developed by the Head-Gordon group,are at the same level of accuracy,and have an root-mean-square deviation (RMSD) of binding energies less than 1 kJ·mol-1 relative to the CCSD(T)/CBS gold standard.The B972-PFD method also showed excellent accuracy in other data set tests.The basis set effect of the B972-PFD method has been benchmarked,and we recommend that the favorable price/performance ratios basis set is Pople's 6-311++G(2d,p).%发现一种与球原子经验色散模型SAM深度契合的杂化泛函B972,组合成高精度的色散校正密度泛函B972-PFD.采用S66、S66x8和S22标准数据集以及大气氢键团簇、Adenine-Thymine的Π…Π堆叠、Watson-Crick氢键复合物和甲烷结合(H2O)20水簇等体系测试了B972-PFD的性能.测试结果显示:对于S66数据集B972-PFD方法的精度与Head-Gordon研究组的三个新泛函ωB97X-V、B97M-V和ωB97M-V处于同一水平,相对于CCSD(T)/CBS金质标准,结合能的RMSD小于1 kJ·mol-1;在其它数据集的测试中,B972-PFD方法也表现出很好的计算精度.通过研究基函数效应,我们推荐Pople的6-31 1++G(2d,p)作为B972-PFD方法的最优性价比基组.
展开▼
