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

The 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 X-2 Pi and A(2)Sigma(+) 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 X-2 Pi -> A(2)Sigma(+) 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 X-2 Pi(1/2) state. [GRAPHICS] .