Quantum chemistry studies of the O K-edge X-ray absorption in WO3 and AWO3

TL;DR

This study compares three first-principles computational approaches to interpret O K-edge X-ray absorption spectra in WO3 and AWO3 perovskites, enhancing understanding of their electronic structure.

Contribution

It provides a comparative analysis of FMS, hybrid DFT, and plane-wave DFT methods for XANES interpretation in WO3-based materials.

Findings

FMS offers accurate local structural insights.

Hybrid DFT captures exchange effects better.

Plane-wave DFT provides efficient electronic structure calculations.

Abstract

In this work we present an interpretation of experimental O K-edge x-ray absorption near edge structure (XANES) in perovskite-type WO3 and AWO3 compounds (A = H and Na) using three different first principles approaches: (i) full-multiple-scattering (FMS) formalism (the real-space FEFF code), (ii) hybrid density functional theory (DFT) method with partial incorporation of exact Hartree-Fock exchange using formalism of the linear combination of atomic orbitals (LCAO) as implemented in the CRYSTAL code; (iii) plane-wave DFT method using formalism of the projector-augmented waves (PAW) as implemented in the VASP code.