van der Waals density functional made accurate

TLDR

The study proposes a van der Waals density functional that improves the description of energetics and geometries of molecules, solids, and adsorption systems compared to the original vdW‑DF. The functional is built on the nonlocal correlation of the second vdW‑DF version and an exchange functional that satisfies the second‑order gradient expansion in the slowly varying limit while reproducing Becke’s large density gradient behavior. A systematic assessment demonstrates the functional’s applicability across a wide range of systems. References cited include Lee et al., Phys.

Abstract

I propose a van der Waals density functional (vdW-DF) that improves upon the description of energetics and geometries of molecules, solids, and adsorption systems over the original vdW-DF. The functional is based on the nonlocal correlation for the second version of the vdW-DF [Lee et al., Phys. Rev. B 82, 081101(R) (2010)] and an exchange functional that recovers the second-order gradient expansion approximation in the slowly varying limit, while reproducing the large density gradient behavior proposed by Becke [J. Chem. Phys. 85, 7184 (1986)]. A systematic assessment of the proposed functional is presented, which demonstrates the applicability of the proposed vdW-DF to a wide range of systems.