A Higher-Accuracy van der Waals Density Functional

TL;DR

The paper introduces vdW-DF2, an improved van der Waals density functional that enhances accuracy in predicting binding energies and structures, enabling more precise calculations in materials science and chemistry.

Contribution

It presents a second version of vdW-DF with a more accurate exchange functional and improved kernel, achieving better agreement with quantum chemical results.

Findings

Close agreement with quantum chemical calculations on 22 duplexes

Improved predictions of binding energies and equilibrium separations

Enhanced applicability to sparse materials in various scientific fields

Abstract

We propose a second version of the van der Waals density functional (vdW-DF2) of Dion et al. [Phys. Rev. Lett. 92, 246401 (2004)], employing a more accurate semilocal exchange functional and the use of a large-N asymptote gradient correction in determining the vdW kernel. The predicted binding energy, equilibrium separation, and potential-energy curve shape are close to those of accurate quantum chemical calculations on 22 duplexes. We anticipate the enabling of chemically accurate calculations in sparse materials of importance for condensed-matter, surface, chemical, and biological physics.