New hydrazinium lanthanide sulphite hydratesPreparation, spectral and thermal properties

Some new hydrazinium lanthanide sulphite hydrates of the formula N2H5Ln(SO3)2(H2O)2 where Ln=La, Pr, Nd and Sm and N2H5Ce(SO3)2 have been prepared and characterized by chemical analyses, magnetic studies and electronic and infrared spectroscopy. Thermal degradation of these complexes has been investigated by simultaneous TG-DTA techniques. These complexes decompose in air after dehydration to give the respective lanthanide sulphate as the final residue. However, cerium complex gives a mixture of cerium sulphate and ceric oxide as the end products. Cerium and neodymium complexes have also been subjected to thermal degradation in nitrogen atmosphere and the dehydration of neodymium complex was observed at a higher temperature than in air. The anhydrous neodymium and cerium complexes decompose in one step to give the respective sulphate in nitrogen atmosphere.