Investigations on transition properties of X1Σ+, A1Σ- , B1Δ, C1Π, D1Σ+, E1Π, and F1Σ+ states of PS+ cation

Ab initio calculations have been performed to study the transition properties of the PS+ cation. Transition dipole moments of fourteen dipole-allowed transitions, between the X-1 Sigma(+), A(1)Sigma(-), B-1 Delta, C-1 Pi, D1 Sigma+, E-1 Pi, and F-1 Sigma(+) states, have been calculated with the aug-cc-pV6Z basis set. Transition probabilities, band origins, as well as radiative lifetimes of vibronic emissions are predicted. The vibrational radiative lifetimes are estimated to be in order of 10(-8) s for the D-1 Sigma(+), F-1 Sigma(+), and first well of E-1 Pi states; 10(-7) s for the C-1 Pi state; 10(-3)-10(-4) s for the second well of E-1 Pi state. Various curve crossings and avoided crossings are revealed with the help of our computed spin-orbit coupling matrix elements. The intricate couplings among different electronic states are analyzed. We propose that the curve crossing with the D-1 Sigma(+) state may be responsible for the fact that the C-1 Pi nu' > 7 vibrational levels cannot be detected in experiment.