Doubly hybrid density functionals that correctly describe both density and energy for atoms.

ABSTRACT: Recently, it was argued [Medvedev MG, et al. (2017) Science 355:49-52] that the development of density functional approximations (DFAs) is "straying from the path toward the exact functional." The exact functional should yield both exact energy and density for a system of interest; nevertheless, they found that many heavily fitted functionals for molecular energies actually lead to poor electron densities of atoms. They also observed a trend that, for the nonempirical and few-parameter functionals, densities can be improved as one climbs up the first four rungs of the Jacob's ladder of DFAs. The XYG3 type of doubly hybrid functionals (xDHs) represents a less-empirical and fewer-parameter functional on the top fifth rung, in which both the Hartree-Fock-like exchange and the second-or

SUBMITTER: Su NQ 

PROVIDER: S-EPMC5878006 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature