ESR of the sulfides of the group IV cations in the qualitative analysis

Abstract

ESR spectra of Mn(II) ions in sulfides of the group IV cations were examined. The sulfides were prepared by the usual precipitation technique using (NH₄)₂S, and the distribution of Mn(II) ion in the precipitates was investigated. Precipitates containing Zn, Co, and Ni together with various amounts of Mn were tested. X-ray powder studies of these mixed sulfides showed amorphous character. No ESR spectrum was observed for nickel sulfide contaminated with manganese (II) ion. ESR hfs was observed for zinc and cobalt sulfides containing small amounts of manganese, and it shows a homogeneous distribution of manganese (II) ion in the precipitation. When treated with 1 N HCl, the ESR hfs of (Co, Mn)S disappeared completely. This probably means the dissolution, and reprecipitation of CoS in process.