Neutron thermodiffractometry study of silver chalcogenide glasses

Silver-containing chalcogenide glasses are of considerable interest for applications in optical and electrical recordings and as solid electrolytes. Therefore, insight in their structural properties is important. A neutron thermodiffraction study of Agx(Ge0.25Se0.75)100−x glasses with x = 15 and 25 at.% was carried out. The amorphous samples were heated in situ from room temperature up to 350 °C, while the neutron diffraction spectra were collected every degree. For both glasses the Ag8GeSe6 phase appeared first, followed by the crystallization of GeSe2. The crystallization process for the Ag-rich glass was more complex with the appearance of a non-identified third phase. Rietveld refinement helped us in studying the evolution of the lattice constants of each phase upon heating.