Molecule-based magnets formed by bimetallic three-dimensional oxalate networks and chiral tris(bipyridyl) complex cations.: The series [ZII(bpy)3][ClO4][MIICrIII(ox)3] (ZII = Ru, Fe, Co, and Ni; MII = Mn, Fe, Co, Ni, Cu, and Zn; ox = oxalate dianion)

synthesis, structure, and physical properties of the series of molecular magnets formulated as [Z(II)(bpy)(3)]-[ClO4][(MCrIII)-Cr-II(ox)(3)] (Z(II) = Ru, Fe, Co, and Ni; M-II = Mn, Fe, Co, Ni, Cu, and Zn; ox = oxalate dianion) are presented. All the compounds are isostructural to the [Ru(bpy)(3)][ClO4][MnCr(ox)(3)] member whose structure (cubic space group P4(1)32 with a = 15.506(2) Angstrom. Z = 4) consists of a three-dimensional bimetallic network formed by alternating M-II and Cr-III ions connected by oxalate anions. The identical chirality (A in the solved crystal) of all the metallic centers determines the 3D chiral structure adopted by these compounds. The anionic 3D sublattice leaves some holes where the chiral [Z(bpy)(3)](2+) and ClO4- counterions are located. These compounds behave as soft ferromagnets with ordering temperatures up to 6.6 K and coercive fields up to 8 mT.