Testing the combination of Hartree-Fock exchange and Wilson-Levy correlation for weakly bonded extended systems

The Wilson-Levy correlation functional is combined with the exact Hartree-Fock exchange in both a posteriori and self-consistent schemes, and applied to a set of weakly bonded extended systems. Crystals of Ne, Ar, C6H6 and graphite, and infinite chains of HF and HCl were selected as a set of representative test cases spanning a range of interaction strengths and types. Results are compared with those obtained from the PBE and PBE0 functionals. This study confirms the good performance of the WL functional, although we conclude that the long-range weak interactions are not properly described in some cases. (C) 2007 Elsevier B.V. All rights reserved.