Evaluation of optical band gaps and dopant state energies in transition metal oxides using oxidation-state constrained density functional theory. (8th July 2021)

• Record Type: Journal Article
• Authors: Ku, Calvin; Sit, Patrick H-L
• Is Part Of: Journal of physics. Volume 33:Number 36(2021)
• Publication Date: 2021-07-08
• Subjects: constrained density functional theory -- transition metal oxides -- band gaps; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/ac0cb8
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: We report the use of oxidation-state constrained density functional theory (OS-CDFT) to calculate the optical band gaps of transition metal oxides and dopant state energies of different doped anatase. OS-CDFT was used to control electron transfer from the valence band maximum of the transition metal system to the conduction band minimum or to the dopant state in order to calculate the band gap or the dopant state energies respectively. The calculation of the dopant state energies also allows identification of the transition responsible for the reduced band gap of the doped system in ambiguous cases. We applied this approach to the band gap calculation in TiO2 anatase and rutile, vanadium pentoxide (V2 O5 ), chromium(III) oxide (Cr2 O3 ), manganese(IV) oxide (MnO2 ), ferric oxide (Fe2 O3 ), ferrous oxide (FeO) and cobalt(II) oxide (CoO). The dopant state energies calculations were carried out in the V-, Cr-, Mn-, and Fe-doped anatase.