Toward Pair Atomic Density Fitting for Correlation Energies with Benchmark Accuracy.

ABSTRACT: Pair atomic density fitting (PADF) has been identified as a promising strategy to reduce the scaling with system size of quantum chemical methods for the calculation of the correlation energy like the direct random-phase approximation (RPA) or second-order Møller-Plesset perturbation theory (MP2). PADF can however introduce large errors in correlation energies as the two-electron interaction energy is not guaranteed to be bounded from below. This issue can be partially alleviated by using very large fit sets, but this comes at the price of reduced efficiency and having to deal with near-linear dependencies in the fit set. One posibility is to use global density fitting (DF), but in this work, we introduce an alternative methodology to overcome this problem that preserves the intrinsically

SUBMITTER: Spadetto E 

PROVIDER: S-EPMC10018742 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature