Analysis of Recent BLYP- and PBE-Based Range-Separated Double-Hybrid Density Functional Approximations for Main-Group Thermochemistry, Kinetics, and Noncovalent Interactions

We investigate the effects of range separation of the exchange energy on electronic ground-state properties for recently published double-hybrid density functionals (DHDFs) with the extensive GMTKN55 database for general main-group thermochemistry, kinetics, and noncovalent interactions. We include the semiempirical range-separated DHDFs omega B2PLYP and omega B2GP-PLYP developed by our group for excitation energies, together with their ground-state-parametrized variants, which we denote herein as omega B2PLYP18 and omega B2GP-PLYP18. We also include the nonempirical range-separated DHDFs RSX-0DH and RSX-QIDH. For all six DHDFs, damping parameters for the DFT-D3 dispersion correction (and for its DFT-D4 variant) are presented. We comment on when the range-separated functionals can be more beneficial than their global counterparts and conclude that range separation alone is no guarantee for overall improved results. We observe that the BLYP-based functionals generally outperform the PBE-based functionals. We finally note that the best- performing DHDFs for GMTKNSS are still the semiempirical range-separated double hybrids omega DSD3-PBEP86-D4 and omega DSD72-PBEP86-D4, the former of which includes a third-order perturbative correlation term in addition to the more conventional secondorder perturbation that DHDFs are based upon.

Automated summary

The study investigated the effects of range separation of exchange energy on electronic ground-state properties for double-hybrid density functionals (DHDFs), observing that specific range-separated functionals can sometimes outperform their global counterparts, but range separation alone does not guarantee overall improved results. It was also noted that BLYP-based functionals generally perform better than PBE-based functionals.