Spectroscopic and transition properties of strontium chloride

The spectroscopic and transition properties of strontium chloride (SrCl) is investigated based on a theoretical approach of ab initio quantum chemistry. The scalar relativistic and spin-orbit coupling (SOC) effect is considered in calculation by introducing Davidson correction, core-valence correlation (CV), The calculation accuracy is improved The results show that the spectroscopic constants of X2Σ+ and A2Π states are consistent with the experimental results. The spectroscopic and molecular constants of most highly excited electronic states have been reported for the first time. The permanent dipole moment (PDMs) and the spin orbit (SO) matrix element have a sudden change for the avoidance of crossing. The potential energy curves (PECs) of the 14 Λ-S states split into 30 Ω states. The splitting energy of A2Π is 290.76 cm-1, which has little difference from the experimental value 295.597 cm-1. Finally, the transition properties are given, including transition dipole moment (TDMs), Franck-Canton factor (FCFs) and radiation lifetime. It is found that the calculated radiation lifetime is in the order of 10ns. The research provides theoretical reference for the feasibility laser cooling of SrCl molecule. The dataset that supported the findings of this study is available in Science Data Bank, including the permanent dipole moment, the spin orbit matrix element and the transition dipole moment .