Syntheses, crystal structures and magnetic properties of three cyanide-bridged iron(III)-manganese(II) binuclear complexes based on dicyanideferrite(III) building blocks.

Three cyanide-bridged Fe-Mn binuclear complexes [Mn(phen)Cl][Fe(bpmb)(CN)]·HO ( 1), [Mn(phen)Cl][Fe(bpdmb)(CN)]·HO ( 2) and [Mn(phen)Cl][Fe(bpClb)(CN)]·3HO·EtOH ( 3) [phen = 1,10-phenanthroline, bpmb = 1,2-bis(pyridine-2-carboxamido)-4-methyl-benzenate, bpdmb = 1,2-bis(pyridine-2-carboxamido)-4,5-dimethyl-benzenate, bpClb = 1,2-bis(pyridine-2-carboxamido)-4-chloro-benzenate)] have been synthesized by the reaction of Mn(phen)Cl with K[Fe(L)(CN)]. The syntheses, crystal structures and magnetic properties of the complexes have been investigated. Single-crystal X-ray diffraction analysis reveals that all three complexes are binuclear complexes and contain Fe-C≡N-Mn linkages. Magnetic investigations indicate antiferromagnetic coupling between low-spin Fe(III) and high-spin Mn(II) centers through cyanide bridging, with J = −1.39(5) cm for 1, J = −3.33(2) cm for 2 and J = −1.96(5) cm for 3. The magneto-structural relationships for cyanide-bridged Fe-Mn systems are discussed based on binuclear Fe-Mn and trinuclear Fe-Mn-Fe magnetic models. [ABSTRACT FROM AUTHOR]