All electron ab initio calculations on the ScTi molecule: a really hard nut to crack

The lightest and yet completely unexplored intermetallic ScTi system has been studied by high-level ab initio methods and quantitative basis sets. We have studied in all 21 2S+1KΛ states and constructed potential energy curves at the MRCI/cc–pvQZ computational level. The ground state of the system is of 6Δ symmetry with r e = 2.65 A and D e = 32.4 kcal/mol with respect to the adiabatic fragments or D e 0 = 10.4 kcal/mol with respect to the ground state atoms while its first excited state seems to be of 4Δ symmetry with similar bonding features lying only 3 kcal/mol higher. An exceptional feature is the rather high Mulliken charge (average value of ~0.5 e-) transferred to Sc but the small calculated dipole moments.