Vanadium pentoxide (V2O5): a van der Waals density functional study

TL;DR

This paper applies van der Waals density functional methods to study the bulk structure of vanadium pentoxide, demonstrating improved accuracy over traditional DFT and discussing methodological considerations.

Contribution

It introduces the use of vdW-DF methods for V2O5, highlighting their advantages and addressing challenges in systems with large vacuum regions.

Findings

vdW-DF improves structural predictions over semilocal DFT

Comparison of different exchange functionals for V2O5

Discussion of issues with vacuum regions in vdW calculations

Abstract

The past few years has brought renewed focus on the physics behind the class of materials characterized by long-range interactions and wide regions of low electron density, sparse matter. There is now much work on developing the appropriate algorithms and codes able to correctly describe this class of materials within a parameter-free quantum physical description. In particular, van der Waals (vdW) forces play a major role in building up material cohesion in sparse matter. This work presents an application to the vanadium pentoxide (V2O5) bulk structure of two versions of the vdW-DF method, a first-principles procedure for the inclusion of vdW interactions in the context of density functional theory (DFT). In addition to showing improvement compared to traditional semilocal calculations of DFT, we discuss the choice of various exchange functionals and point out issues that may arise when treating systems with large amounts of vacuum.