On complex selenites of scandium

The conditions have been studied of obtaining complex selenites of scandium of the type MSc(SeO3)2 x nH2O(M-Li, Na, K, Rb, Cs, NH4; n = 1-25) from aqueous solutions at different concentrations of the initial reagents and acidity of the medium. Several methods of synthesis have been proposed; all the compounds have been separated in a solid state. The pH value of the formation of the compounds somewhat decreases in the series Li-Na-NH4-K-Rb-Cs. Complex compounds, with the exception of a potassium compound, are decomposed by water. The decomposition degree increases from Na to Cs