Magnetic Studies in Mixed-Metal Valency Molecule Magnets NBu4FeιιnMnιι1-n[Feιιι(OX)3](n=0.03, 0.10, 0.15, 0.97)

The mixed valency character and antiferromagnetic coupling in Molecule magnets Materials NBu4FeIInMnII1-n[FeIII(OX)3]（n=0.03、0.10、0.15、0.97） were investigated by magnetic measurements.The values of M increase and exhibit weak irreversibility in the field-cooled (FC) magnetization curves. There are a clear bifurcation phenomenon of the field-cooled (MFC) and Zero-field-cooled (MZFC) magnetization curves.In the Molecule magnets Materials NBu4FeII0.10 MnII0.90[FeIII(OX)3],the Ne´el temperature is 34 K.And the Ne´el temperature of NBu4FeII0.15MnII0.85 [FeIII(OX)3] is 28 K.In the sample NBu4FeII0.03 MnII0.97[FeIII(OX)3],,the bifurcation of the ZFC and FC plots below the Ne´el temperature of 30 K indicates irreversibility.The oxalate group has been shown to be an excellent bridging ligand in supporting the magnetic exchange interaction.