Magnetic properties of five planar defect dicubanes of [LnIII4(渭3-OH)2(L)4(HL)2]路2THF (Ln = Gd, Tb, Dy, Ho and Er)
文摘
A series of five isostructural tetranuclear defect dicubane, or butterfly, topology 4f coordination clusters of formula [LnIII4(渭3-OH)2(L)4(HL)2]路2THF, [H2L = (E)-2-(2-hydroxy-3-methoxybenzylideneamino)phenol; Ln = Gd(1), Tb(2), Dy(3), Ho(4) and Er(5)) has been synthesized and characterized. The highly anisotropic Dy4 and Ho4 complexes clearly show intramolecular ferromagnetic coupling which arise from dominant intramolecular dipolar-dipolar interactions rather than any significant superexchange effects. Furthermore, the Dy4 complex shows Single Molecule Magnet (SMM) behavior.