ELECTRON PARAMAGNETIC RESONANCE STUDIES ON SOME TUTTON SALT SYSTEMS

Abstract

Electron paramagnetic resonance (EPR) studies were carried out on a vanadyl doped mixed Tutton salt (Zn 0.25 Mg 0.75 (NH 4 ) 2 (SO 4 ) 2 .6H 2 O) system. The “g” and “A” parameters obtained from our studies were compared with other vanadyl doped Tutton salts and a critical analysis is presented. As the EPR results depend upon the vicinity of V 4+ of doped V=O ion in the host, the ‘g’ and ‘A’ parameters obtained from our studies reflect distorted octahedral surroundings of V 4+ in the Tutton salt host and two major types of metal –water linkages are established. Our findings are supported by the X-ray studies and electric field assisted de-aquation studies on Tutton salts by the earlier works. Critical analysis and correlation of the results indicate that the equatorial bonds and axial bonds between the oxygen of water molecules and the divalent cation in Tutton salts are of different nature, confirming that the octahedron formed by water molecules around the divalent ion in Tutton salts is distorted.