Ab initio study of the lowest-lying electronic states of LuCl molecules.

By using the CASSCF/MRCI methods, the theoretical electronic structure of the LuCl molecule has been investigated. These methods have been performed for 20 singlet and triplet electronic states in the representation (2s+1)Λ((±)). Calculated potential energy curves (PECs) are also displayed. Spectroscopic constants including the harmonic vibrational wavenumber ω(e) (cm(-1)), the relative electronic energy T(e) (cm(-1)) referred to the ground state, and the equilibrium internuclear distance R(e) (Å) have been predicted for all of the singlet and triplet electronic states situated below 43,000 cm(-1). Spin-orbit effects have also been taken into consideration and calculated for the lowest-lying electronic states in the representation Ω((±)).