Theoretical study on the low-lying electronic states of SbF

Multi-reference configuration interaction calculations are carried out to elucidate the distribution of lowlying valence and Rydberg states of antimony monofluoride (SbF) below 50000 cm-1, where the effects of core-valence correlation and spin-orbit coupling have been employed. From the potential energy curves, the spectroscopic constants of seven (quasi-)bound Lambda-S and fourteen (quasi-)bound Q states have been derived, which agree well with the experimental values. Our results show that the second 3H state involves the occupation on the Rydberg shell 6s of Sb, which settles the assignment of the so-called "C2" and "C31" states in the ultraviolet spectra of SbF. With the help of the more accurate coupled cluster calculations, the dissociation energy (De) of SbF is determined to be 4.24 eV at the theoretical limit, being 0.2 eV smaller than the widely used empirical value in the literature.