Ab initio study: the potential energy curves and ro-vibrational spectrum of low-lying excited states of HCl+ cation

Abstract

ABSTRACTThe potential energy curves (PECs) of 11 electronic states of HCl+ cation are obtained by using the high-level relativistic multi-reference configuration interaction plus Davidson correction (MRCI + Q) method. The spin-orbit coupling effect is also taken into account in electronic structure calculations. The PECs of X2Π and A2Σ+ states accord well with corresponding Rydberg--Klein–Rees PECs. The spectroscopic constants for the bound states of HCl+ agree well with available theoretical and experimental data. The dipole moments (DMs) and transition dipole moment of the X2Π→A2Σ+ are also in agreement with previous results. According to the PEC and DM, we calculated Einstein A-coefficients and ro-vibrational line intensities of 1–0, 2–0, 2–1, 3–0, 3–1, 4–0 and 4–1 bands for X2Π1/2 state.