A rare ferromagnetic manganese(III) hexanuclear cluster

The reaction of salicylaldoxime (H2sao) with Mn(ClO4)2·6H2O, sodium 3,5-dinitrobenzoate and NEt4(OH) in MeOH/EtOH affords a MnIII hexanuclear compound [Mn6O2(sao)6(ArCO2)2(MeOH)2(EtOH)2(H2O)2] (ArCO2H = 3,5-dinitrobenzoic acid) (1). 1 contains [MnIII6(µ3-O)2]14+ core, with a known structural type in the family of Mn6 clusters. Temperature-dependent magnetic susceptibility study shows presence of predominant ferromagnetic interactions between MnIII ions. Alternating current (ac) susceptibility measurements reveal a frequency-dependent out-of-phase (χM′′) signal below 4 K, suggesting 1 to be a single-molecule magnet (SMM).