Characterizing electronic states and spectra in transition metal-rare gas diatomic cations: The cases of VAr+ and VKr+

Abstract

Nine low-lying quintet electronic states of the cations VAr+ and VKr+ are characterized theoretically at the SA-CASSCF/icMRCI/aug-cc-pV5Z level of theory by the construction of potential energy curves and the determination of spectroscopic parameters. The polarity of the molecules is described by dipole moment functions and vibrationally averaged dipole moments. Transition probabilities for spontaneous emission for selected states are estimated by the Einstein Av´,v´´ coefficients and the stronger transitions identified; radiative lifetimes are also reported. For the photoabsorption process, the spectrum is modelled for the bands of the G 5Π – X 5Σ+ system of each species for which experimental photodissociation results are available in the literature. Not known experimentally, the intensity distribution is expected to help elucidate the assumed vibrational numbering of the upper state, and together with the overall electronic description and spectroscopic parameters motivate further experimental investigations of transition metal-rare-gas cations. Binding arises from purely electrostatic charge-induced dipole interaction.