Synthesis of Isomeric Tb3+-Phthalocyanine Double-Decker Complexes Depending on the Difference in the Direction of Coordination Plane and Their Magnetic Properties

A C symmetrically substituted phthalocyanine, 1,8,15,22-tertrakis(2,4-dimethylpent-3-oxy)phthalocyanine (H TdMPPc), was used to synthesize Tb -phthalocyanine double-decker complexes ([Tb(TdMPPc) ]s). Because H TdMPPc has C symmetry, S,S, R,R, and meso isomers of [Tb(TdMPPc) ] were obtained depending on the difference in the direction of the coordination plane of two C -type phthalocyanines with respect to a central Tb ion. We investigated the physical properties of these [Tb(TdMPPc) ] isomers, including their single-ion magnetic properties, and found that the spin-reversal energy barrier (U ) of the meso isomer was apparently higher than that of the enantiomers. Detailed crystal structural analyses indicated that the meso isomer has a more symmetrical structure than do the enantiomers, thereby suggesting that the higher U of the meso isomer originated from the more highly symmetrical structure.