The hyperfine structure branching ratios and ab initio study on low-lying electronic states for MgF molecule.

The potential energy curves (PECs) of the fourteen low-lying Λ-S electronic states, spectroscopic constants, transition properties for the MgF molecule are calculated at the multi-reference configuration interaction level of theory. The spin-orbit coupling effects are also taken into account in the electronic structure calculations. Spectroscopic constants agree well with previously obtained theoretical and experimental values. Based on the potential energy curves and transition dipole moments, the highly diagonally distributed Franck-Condon factors (f = 0.975, f = 0.926) for the AΠ (v' = 0, 1) → XΣ (v″ = 0, 1) transition are determined. Moreover, it is important to note that the dissociation energy (2.68 eV) of the BΣ state is achieved for the first time. Then, employing a quantum effective Hamiltonian approach, we investigate the hyperfine structure branching ratios between the AΠ state and the XΣ state. And the numerically analyze is obtained for a simple one-dimension (1D) case on MgF molecular MOT. We hope that these data can provide a helpful reference for the assignment and analysis of guiding further experimental spectroscopic measurements and laser cooling in experimental on the MgF molecule.