Two one-dimensional compounds based on pyramidal {TbCu4} units and formate ligand: chair-like [(H2O)2(ClO4)2]2- clusters and slow relaxation of magnetization

With formate as ligand, two 1-D 3d-4f compounds (linear and zigzag) based on pyramidal {TbCu4} unit were obtained. Chair-like [( H2O)(2)(ClO4)(2)](2-) clusters and mu(5)-eta(1):eta(4) bridging mode of formate were observed in the linear one which also displays slow relaxation of the magnetization.