Magnetic exchange coupling in transition metal complexes with bidentate bridging ligands: a quantum chemical study

摘要

The exchange couphng constants (J) were calculated and the spin density distributions were analyzed in the B3LYP/TZV approximation for the complex anions [L2M(1)~(III)LM(2)~(II)L2]~(n-1), where L is ligand (L is oxalate, oxamide, dithiooxamide, hydroxamate) and M(l) and M(2) are atoms of the tri- and divalent 3d-transition metals, respectively, and n- is the charge of the anion. The largest J values were found for the complexes formed by the Cr~(III)-Ni(II) and Cr~(III)-Co~(II) pairs with the dithiooxamide ligands. Differences between the calculated and experimental J values are at most a few cm~(-1).