Three binuclear Nd(Ⅲ)-Nd(Ⅲ), Dy(Ⅲ)-Dy(Ⅲ) and Ho(Ⅲ)-Ho(Ⅲ) complexes containing the dianion of chloranilic acid (CA) as bridging ligand have been synthesized, namely Ln2(Phen)4(CA)(NCS)4(Ln = Nd, Dy, Ho; Phen=l, 10-phenanthroline; CA = dianion of chloranilic acid). They have been characterized by elemental analyses, IR and electronic spectra, conductance and variable-temperature magnetic susceptibility. The observed susceptibility data were fit to those from theoretical magnetic equation by least-squares meth...