Řezáč Jan, Huang Yuanhang, Hobza Pavel, Beran Gregory J O
Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic , 166 10 Prague, Czech Republic.
Department of Chemistry, University of California , Riverside, California 92521 United States.
J Chem Theory Comput. 2015 Jul 14;11(7):3065-79. doi: 10.1021/acs.jctc.5b00281.
Many-body noncovalent interactions are increasingly important in large and/or condensed-phase systems, but the current understanding of how well various models predict these interactions is limited. Here, benchmark complete-basis set coupled cluster singles, doubles, and perturbative triples (CCSD(T)) calculations have been performed to generate a new test set for three-body intermolecular interactions. This "3B-69" benchmark set includes three-body interaction energies for 69 total trimer structures, consisting of three structures from each of 23 different molecular crystals. By including structures that exhibit a variety of intermolecular interactions and packing arrangements, this set provides a stringent test for the ability of electronic structure methods to describe the correct physics involved in the interactions. Both MP2.5 (the average of second- and third-order Møller-Plesset perturbation theory) and spin-component-scaled CCSD for noncovalent interactions (SCS-MI-CCSD) perform well. MP2 handles the polarization aspects reasonably well, but it omits three-body dispersion. In contrast, many widely used density functionals corrected with three-body D3 dispersion correction perform comparatively poorly. The primary difficulty stems from the treatment of exchange and polarization in the functionals rather than from the dispersion correction, though the three-body dispersion may also be moderately underestimated by the D3 correction.
多体非共价相互作用在大型和/或凝聚相系统中变得越来越重要，但目前对于各种模型预测这些相互作用的能力的理解是有限的。在此，已进行基准完全基组耦合簇单双激发和微扰三激发（CCSD(T)）计算，以生成一个用于三体分子间相互作用的新测试集。这个“3B - 69”基准集包括69个三聚体结构的三体相互作用能，由23种不同分子晶体中每种的三个结构组成。通过纳入展现各种分子间相互作用和堆积排列的结构，该集合为电子结构方法描述相互作用中涉及的正确物理过程的能力提供了严格测试。MP2.5（二阶和三阶Møller - Plesset微扰理论的平均值）和用于非共价相互作用的自旋分量缩放CCSD（SCS - MI - CCSD）表现良好。MP2能较好地处理极化方面，但它忽略了三体色散。相比之下，许多用三体D3色散校正的广泛使用的密度泛函表现相对较差。主要困难源于泛函中交换和极化的处理，而非色散校正，尽管三体色散也可能被D3校正适度低估。
