Accurate spectroscopic calculations of the 14 Λ-S and 30 Ω states of BF+ cation including the spin-orbit coupling effect

This paper studied the PECs of 14 Λ-S states and 30 Ω states of the BF+ cation for internuclear separations from 0.08 to 1.10 nm. The calculations were done using the CASSCF method followed by the icMRCI approach with the aug-cc-pV6Z basis set. Of these 14 Λ-S states, the 24Σ+ and 24Π states were repulsive. The 22Π and 32Π states had double well. The avoided crossings were found between the 12Π and 22Π states, and between the 32Π and 42Π states. The 12Π, 22Π, 32Π, and 14Π states were inverted with the SOC effect taken into account. The 14Π state and the second wells of 22Π and 32Π states were weakly bound. Each of the 12Π, 22Π and 32Π states had one barrier. All the PECs were extrapolated to the CBS limit. Core-valence correlation and scalar relativistic corrections were included. The SOC effect was included. The spectroscopic parameters were determined. Comparison with available experimental data show that the methodology used is highly accurate for this system.117