Syntheses, crystal structures and magnetic properties of two low-dimensional cyano-bridged CrIII–MnII/III assemblies

Abstract

Two low-dimensional cyano-bridged CrIII–MnII/III assemblies {[Mn(salpn)][Cr(CN)6]}n·2n[Mn(salpn)(CH3OH)2]·2nH2O (1) (salpn = N,N′-1,2-propylenebis(salicylideneiminato)dianion) and {[Mn(bipy)2]2(H2O)Cl}[Cr(CN)6]·2H2O (2) (bipy = 2,2′-bipyridine) have been synthesized and characterized by thermal analyses, single crystal X-ray structural analyses and magnetic measurements. Complex 1 consists of [(CN)5CrIII–CN–MnIII(salpn)]n2n− anionic chains, isolated [MnIII(salpn)(CH3OH)2]+ cations, and crystallized water molecules. Each [Cr(CN)6]3− unit connects two adjacent [MnIII(salpn)]+ moieties through trans-cyano groups, resulting in the formation of an anionic one-dimensional (1-D) wave-like chain. Complex 2 is composed of trinuclear clusters of {[Mn(bipy)2]2(H2O)Cl}[Cr(CN)6] and guest water molecules. In the trinuclear entity, the [Cr(CN)6]3− unit connects two neighboring [MnII(bipy)2(H2O)0.5Cl0.5]1.5+ moieties in a trans fashion through two cyano ligands. Magnetic studies reveal that complexe 1 behaves as a ferrimagnet with critical temperature Tc of 4.5 K resulted from the interchain magnetic interactions, while complex 2 exhibits intramolecular antiferromagnetic coupling.