121Sb Mössbauer studies on some antimony III chalcogenides and chalcogenohalides. Application to the structural approach of sulfide glasses

This study concerns antimony chalcogenides and iodochalcogenides isolated in the systems: M¹ ₂S-Sb₂S₃ (M^I=Li, Tl), Sb₂X₃-SbI₃, SnX-SbI₃ (X=S, Se, Te) and Sb Se –Sb Te. The crystal structure determination of these compounds was carried out. As all elements with pair antimony III atoms show varied environments by sulphur and iodine atoms in terms of activity of its 5s² non-bonding electron. Mössbauer effect of¹²¹Sb leads to the determination of the local electron environment and to complete the crystal structure analysis. Evolution of Mössbauer data is related to antimony III environment type, bond lengths and activity of non-bonding electron pair. These results have been used to give a structural approach of glass forming region in the Tl₂S-Sb₂S₃ system.