Synthesis and Magnetic Properties of Novel Nickel (II) and Terbium (III)-Dipyridyl Coordination Bridged Polysilsesquioxane

A novel bipyridine-bridged polysilsesquioxane was synthesized and its metal-coordination polymers were prepared by sol-gel technology from bipyridine-bridged silsesquioxane and the nickel salt (nickel acetate) or terbium salt (terbium chloride) under the catalysis of diluted hydrochloric acid. The structures of polymer and metal-coordination polymer were verified with infrared ray spectrometry, ultraviolet spectrometry and elemental analysis. Meanwhile, the scanning electron microscope (SEM) results suggested that the homogeneous and spherical particles were formed. Finally, The magnetic properties of the two coordinated polymers were tested. The results show that both exhibited ferromagnetism in low temperature. Ni(2+)-coordination polymer was a hard-ferromagnet due to its large values of coercive force, remanent magnetization and area of magnetic hysteresis loop. However, Tb(3+)-coordination polymer was a soft-ferromagnet ascribed to its small values of coercive force, remanent magnetization and area of magnetic hysteresis loop.