Santra Golokesh, Bursch Markus, Wittmann Lukas
Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
Interdisciplinary Center for Scientific Computing, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 205, 69120 Heidelberg, Germany.
J Phys Chem A. 2025 Aug 7;129(31):7218-7228. doi: 10.1021/acs.jpca.5c01035. Epub 2025 Jul 24.
We investigate the potential performance improvements of double-hybrid density functionals by replacing the standard scaled opposite-spin MP2 (SOS-MP2) with the modified opposite-spin-scaled MP2 (MOS-MP2) in the nonlocal correlation component. Using the large and diverse GMTKN55 data set, we find that MOS-double hybrids provide significantly better accuracy compared to SOS-MP2-based double hybrids when empirical dispersion correction is not employed. The noncovalent interaction subsets account for the majority of this improvement. However, when the D4 dispersion correction is applied, the performance gap between MOS-MP2- and SOS-MP2-based double hybrids becomes negligible. While the new methods do not outperform the current state-of-the-art double hybrid functionals, our study offers valuable insights into the applicability of distance-dependent MP2 in place of conventional SOS-MP2, as well as the critical role of empirical dispersion corrections in further enhancing accuracy─insights that are useful for guiding future method developments. For nine transition metal sets, dispersion-corrected spin-component-scaled double hybrids are still significantly better than any MOS-double hybrid functional.
我们通过在非局部相关分量中用修正的反自旋缩放MP2（MOS-MP2）取代标准的缩放反自旋MP2（SOS-MP2），研究了双杂化密度泛函的潜在性能改进。使用庞大且多样的GMTKN55数据集，我们发现，在不采用经验色散校正时，与基于SOS-MP2的双杂化泛函相比，基于MOS的双杂化泛函具有显著更高的精度。非共价相互作用子集占了这一改进的大部分。然而，当应用D4色散校正时，基于MOS-MP2和基于SOS-MP2的双杂化泛函之间的性能差距变得可以忽略不计。虽然新方法没有优于当前最先进的双杂化泛函，但我们的研究为距离依赖型MP2取代传统SOS-MP2的适用性，以及经验色散校正在进一步提高精度方面的关键作用提供了有价值的见解——这些见解有助于指导未来的方法开发。对于九个过渡金属集，色散校正的自旋分量缩放双杂化泛函仍然明显优于任何基于MOS的双杂化泛函。
