A b i n i t i o calculations of radiative transition probabilities in SH, SH+, and SH−

Abstract

Potential energy and dipole moment functions for the ground states of SH, SH+, and SH− have been calculated from highly correlated electronic wave functions. The electric dipole moments in the vibrational ground states of 3 2SH, 3 2SH+, and 3 2SH− are calculated to be 0.74, 1.29, and 0.27 D, and the rotationless rates of spontaneous emission A 1 0 to be 1, 52, and 75 s− 1, respectively. The predicted transition probabilities between the low lying vibrational states of the electronic ground state of SH and SD are among the smallest so far known for dipole allowed rotation‐vibration transitions. The calculated A–X transition probabilities in SH confirm recent indirect determinations of the radiative lifetimes and absorption oscillator strengths in the predissociating v’=0 level of the A state. The 4Σ− state is calculated to intersect the A 2Σ+ state at R=3.1 a.u., between the classical turning points of v’=0 and 1 in the A state.