Dual-hybrid direct random phase approximation and second-order screened exchange with nonlocal van der Waals correlations for noncovalent interactions

We have added the nonlocal van der Waals correlation energy functional of Vydrov and Van Voorhis in 2010 (VV10NL) to the dual-hybrid direct random phase approximation (dRPA75) and second-order screened exchange (SOSEX75) for noncovalent interactions. The obtained methods are denoted as dRPA75-NL and SOSEX75-NL, and the corresponding short-range attenuation parameters are fitted with the large aug-cc-pV5Z basis set against the S66 dataset. Therefore, the dRPA75-NL method overcomes the error cancellation problem of the dRPA75 method with the relatively small aug-cc-pVTZ basis set for noncovalent interactions. Based on our benchmark computations, the dRPA75-NL and SOSEX75-NL methods perform very well on evaluating noncovalent interaction energies. Compared with the double-hybrid density functionals (DHDFs) of DSD-PBEP86-NL and DOD-PBEP86-NL, the dRPA75-NL and SOSEX75-NL methods perform much better on charge transfer interactions. Furthermore, the SOSEX75-NL method also gives insight into the development of computational methods for both closed-shell and open-shell noncovalent interactions. In summary, our computations demonstrate that even the full dRPA and SOSEX correlations still need additional dispersion corrections for noncovalent interactions.