The low-lying electronic states of VO₄ and VO₄^–: a computational study

Abstract

Vanadium tetraoxide (VO₄) has several isomers, and VO₂(η²-O₂) is the most stable one. The low-lying doublet states of VO₂(η²-O₂) and low-lying singlet states of VO₂(η²-O₂)⁻ were studied using the SAC-CI theory. The electron detachment energies from the ground electronic state of VO₂(η²-O₂)⁻ to the low-lying doublet states of VO₂(η²-O₂) were obtained. These electron detachment energies can be compared with the previous experimental photoelectron spectrum of VO₄⁻, and possible candidate states for the unassigned bands were found. The ground electronic states of VO₂(η²-O₂)/VO₂(η²-O₂)⁻ and seven doublet excited states of VO₂(η²-O₂) were optimised. The vertical excitation spectra of VO₂(η²-O₂) and VO₂(η²-O₂)⁻ were calculated. The lowest doublet/quartet states of VO₄ and lowest singlet/triplet states of VO₄^– were also computed at the BP86/aug-cc-pVTZ level.

Highlights

• VO₂(η²-O₂) is the most stable isomer of VO₄. The low-lying electronic states of VO₂(η²-O₂) and VO₂(η²-O₂)⁻ were calculated using the SAC-CI theory. The unassigned bands in previous photoelectron spectrum of VO₄^– were assigned, and the main structures of this spectrum can be described by the electron detachments from VO₂(η²-O₂)⁻ to the low-lying doublet states of VO₂(η²-O₂).

• The computational results presented in this study were useful for the spectroscopic studies of VO₄/VO₄^–. Knowledge obtained in this study would be also helpful in understanding the electronic structures of MO₄/MO₄^– (M = Metal).

GRAPHICAL ABSTRACT

KEYWORDS:

• Vanadium tetraoxide
• VO₄
• VO₄⁻ anion
• electronic states
• electron detachment energies

Acknowledgements

The author thanks to National Centre for High-performance Computing (NCHC) for providing computational and storage resources.

Disclosure statement

No potential conflict of interest was reported by the author(s).