{Mn₆^IIIMn^IVDy₂^III} Single-Molecule Magnet Based on Cubane Subunits

A new mixed-valence heterometallic nonanuclear cluster [Mn7Dy2(μ4-O)2(μ3-O)4(μ3-OMe)2(μ2-OH)(piv)8(dea)2(MeOH)2(H2O)2](NO3)·H2O (1) (where Hpiv = pivalic acid) was prepared from the reaction of Mn(piv)2 with Dy(NO3)3·6H2O and diethanolamine (H2dea) in a MeOH/CH2Cl2 mixture. The C2-symmetric cluster comprises an unprecedented {Mn6IIIMnIVDy2III}28+ core consisting of two distorted {Mn2IIIMnIVDyIIIO4} cubane moieties sharing a common MnIV vertex and decorated with two additional MnIII atoms. Hirshfeld surface analysis and fingerprint plots are used for decoding the intermolecular interactions in 1. Magnetic studies indicate that 1 exhibits a slow relaxation behavior with an effective energy barrier of 15.2 K and τ0 = 1.4 × 10–7 s.