Cyanide-Bridged CrIIIMnII Binuclear Complexes Based on [Mn(phen)2]2+ and Dicyanidechromate(III) Building Blocks: Syntheses, Crystal Structures, and Magnetic Properties

Three new cyanide-bridged (CrMnII)-Mn-III binuclear complexes, [Mn(phen)(2)Cl][Cr(bpmb)(CN)2]center dot H2O (1) (phen = 1,10-phenanthroline, bpmb(2-) = 1,2-bis(pyridine-2-carboxamido)-4-methyl-benzenate), [Mn(phen)(2)Cl][Cr(bpdmb)(CN)2]center dot H2O (2) (bpdmb(2-) = 1,2-bis(pyridine-2-carboxamido)-4,5-dimethyl-benzenate), and [Mn(phen)(2)Cl][Cr(bpClb)(CN)(2)]center dot CH3OH center dot H2O (3) (bpClb(2-) = 1,2-bis(pyridine-2-carboxamido)-4-chloro-benzenate) were obtained based on Mn(phen)(2)Cl-2 and a series of dicyanidechromate(III) building blocks. Single crystal X-ray diffraction analysis shows the structures of the three complexes are dimeric type with two different metal centers linked by a cyanide group from corresponding dicyanidechromate(III) building block. Magnetic investigations indicate the existence of relatively weak antiferromagnetic coupling between Cr(III) and Mn(II) ions with best-fit constants J(CrMn) = -2.78(5) cm(-1) for 1, J(CrMn) = -3.02(2) cm(-1) for 2 and J(CrMn) = -2.27(3) cm(-1) for 3 based on the spin exchange Hamiltonian = -2J(CrMn)(S) over cap (cr) (S) over cap (Mn). The magneto-structural correlation of cyanide-bridged (CrMnII)-Mn-III complexes has been discussed at last.