Short range DFT combined with long-range local RPA within a range-separated hybrid DFT framework

Selecting excitations in localized orbitals to calculate long-range correlation contributions to range-separated density-functional theory can reduce the overall computational effort significantly. Beyond simple selection schemes of excited determinants, the dispersion-only approximation, which avoids counterpoise-corrected monomer caculations, is shown to be particularly interesting in this context, which we apply to the random-phase approximation. The approach has been tested on dimers of formamide, water, methane and benzene.