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).