Cohesive properties of noble metals by van der Waals-corrected Density Functional Theory

TL;DR

This paper evaluates various van der Waals-corrected density functional theory methods to accurately compute the cohesive properties of noble metals, highlighting the importance of screening effects and many-body interactions.

Contribution

It introduces new methods incorporating dynamical screening effects and compares their performance with traditional approaches for noble metals.

Findings

Van der Waals interactions significantly influence noble metals' properties.

New methods effectively include screening effects in DFT calculations.

Many-body effects are quantitatively assessed within the RPAp approach.

Abstract

The cohesive energy, equilibrium lattice constant, and bulk modulus of noble metals are computed by different van der Waals-corrected Density Functional Theory methods, including vdW-DF, vdW-DF2, vdW-DF-cx, rVV10 and PBE-D. Two specifically-designed methods are also developed in order to effectively include dynamical screening effects: the DFT/vdW-WF2p method, based on the generation of Maximally Localized Wannier Functions, and the RPAp scheme (in two variants), based on a single-oscillator model of the localized electron response. Comparison with results obtained without explicit inclusion of van der Waals effects, such as with the LDA, PBE, PBEsol, or the hybrid PBE0 functional, elucidates the importance of a suitable description of screened van der Waals interactions even in the case of strong metal bonding. Many-body effects are also quantitatively evaluated within the RPAp approach.