Magnetic coupling interaction for mixed transition metal dimer: Ab initio MRCI(SD)Â +Â Q investigation on CrCu

Ab initio calculations on the potential energy curves and electronic structures of the ground and low-lying electronic states for the CrCu dimer have been carried out by using the MRCI(SD) + Q method. The results presented the 6Σ+ ground state, by contrast to the assigned ground state 4Σ in ESR of CrCu, and the ground state 6Σ+ is mainly dominated by strong intra-atomic d-d exchange interactions on the atom Cr.