Electronic structure of SrO molecules with dipole moments and ro-vibrational calculations

Abstract

Ab initio calculations have been applied to investigate the electronic structure of the SrO molecule. The potential energy curves have been computed in the Born–Oppenheimer approximation for the ground, and the 29 low-lying singlet and triplet excited electronic states. Complete active space self-consistent field, multi-reference configuration interaction have been utilized to investigate these states. The harmonic frequency ωe, the internuclear distance Re, the rotational constant Be, and the electronic energy with respect to the ground state Te have been calculated by using two different techniques of calculation with different bases. The transition dipole moment between some doublet states is used to determine the Einstein spontaneous A21 and induced emission coefficients as well as the spontaneous radiative lifetime τspon, emission wavelength λ21 and oscillator strength f21. The eigenvalues Ev, the rotational constant Bv, the centrifugal distortion constant Dv, and the abscissas of the turning points Rmin and Rmax have been calculated by using the canonical functions approach. The comparison between the values of the present work and those available in the literature for several electronic states shows a very good agreement. Twenty-four new electronic states have been studied here for the first time.