Nano-sized tetralanthanoid-copper complex ions containing oximato bridges

Complexation of LnIII(hfac)3, LnIII(OAc)3, and [CuII(dmg)2]2− in the presence of Ph4P+ gave [Ln4Cu1]-type pentanuclear complexes (dmg = dimethylglyoximate dianion; Ln = La, Nd, Eu, Gd, Tb). Single-crystal X-ray diffraction analyses revealed that four Ln(IIl) ions formed a rectangular array around the copper ion at its inversion center. The [Ln4Cu1] core structures are essentially the same regardless of the different Ln ions. From the magnetic susceptibility measurements, the Cu(dmg)2 dianion moiety has been shown to play a role of the ferrimagnetic coupler among the Gd spins. The out-of-phase ac susceptibility of the [Tb4Cu1] complex exhibited anomalous frequency- dependence below 4 K, indicating blocking behavior potentially related to a single-molecule magnet.