Mapping mechanism between density of states and ultraviolet-visible light absorption spectra

TL;DR

This study establishes a method to relate the density of states in materials to their UV-vis absorption spectra, verified experimentally on BiOIO3, offering a new way to connect theoretical DFT data with optical properties.

Contribution

It introduces a novel mapping approach from density of states to UV-vis spectra, bridging DFT calculations with experimental optical observations.

Findings

Successful construction of DOS to UV-vis spectra mapping.

Experimental verification on BiOIO3 semiconductor.

Highlighting the limitations of using VBM-CBM difference for band gap estimation.

Abstract

This paper constructs the mapping relation from density of states (DOS) to UV-vis spectra by using an ab initio perspective. Taking BiOIO3 semiconductor photocatalyst as an example, the experimental verification was also carried out. The optical response of the material considers the superposition benefits of all possible transitions. Directly using the difference between valence band maximum (VBM) and conduction band minimum (CBM) will lead to an underestimate of the energy band gap. This paper provides a new idea of linking the density functional theory (DFT) data with experiment phenomenon.