Van der Waals density-functional theory study for bulk solids with BCC, FCC, and diamond structures

TL;DR

This study evaluates various van der Waals density functionals by calculating structural properties of bulk solids with different crystal structures to assess their reliability and guide future materials research.

Contribution

It provides a comprehensive assessment of vdW functionals for bulk solids, aiding the development and selection of more accurate methods in DFT simulations.

Findings

Different vdW functionals show varying accuracy in predicting lattice constants.

Some vdW methods reliably estimate bulk moduli and cohesive energies.

Results inform the choice of vdW functionals for specific material types.

Abstract

Proper inclusion of van der Waals (vdW) interactions in theoretical simulations based on standard density functional theory (DFT) is crucial to describe the physics and chemistry of systems such as organic and layered materials. Many encouraging approaches have been proposed to combine vdW interactions with standard approximate DFT calculations. Despite many vdW studies, there is no consensus on the reliability of vdW methods. To help further development of vdW methods, we have assessed various vdW functionals through the calculation of structural prop- erties at equilibrium, such as lattice constants, bulk moduli, and cohesive energies, for bulk solids, including alkali, alkali-earth, and transition metals, with BCC, FCC, and diamond structures as the ground state structure. These results provide important information for the vdW-related materials research, which is essential for designing and optimizing materials systems for desired physical and chemical properties.