Bimetallic Materials Derived from Manganese(III) Schiff Base Complexes and Pentacyanidonitrosylferrate(II) Precursor: Structures and Magnetic Properties

Abstract

Three complexes, [Mn(salphen)(H(2)O)](2)[Fe(CN)(5)(NO)] x 2 CH(3)OH (1) (salphen = N,N'-phenylenebis(salicylideneiminato) dianion), [Mn(naphtmen)(CH(3)OH)](2)[Fe(CN)(5)(NO)] (2) (naphtmen = N,N'-(1,1,2,2-tetramethylethylene)bis(naphthylideneiminato) dianion), and {[Mn(salen)](2)[Fe(CN)(5)(NO)] x H(2)O}(n) (3) (salen = N,N'-ethylene-bis(salicylideneiminato) dianion), were synthesized and structurally characterized by X-ray single-crystal diffraction. The structural analyses show that complexes 1 and 2 consist of the discrete linear trinuclear [Mn(SB)](2)[Fe(CN)(5)(NO)] units (SB = salphen for 1, naphtmen for 2); in complex 3, the nitroprusside anion coordinates to the axial sites of the four [Mn(salen)](+) entities through its four cyano nitrogen atoms, providing a two-dimensional network. The magnetic analysis indicates that the nitroprusside bridging ligand propagates a very weak antiferromagnetic exchange and single-ion anisotropy (D) plays an important role in the overall magnetic properties. Different from complexes 2 and 3, complex 1 shows a typical spin-flop transition with a critical field of 20 kOe.