Structures and thermal properties of silver(I) (Poly)chalcogenide halide solid solutions Ag₁₀Te_{4-(q, p)}Q_{(q, p)}Br ₃ with Q = S, Se

X-Ray diffraction experiments, thermal analyses and EDX spectroscopy were performed to determine the structural and thermal properties of the solid solutions Ag₁₀Te_4-qS_qBr₃ and Ag ₁₀Te_4-pSe_pBr₃. The present investigation completes the work on silver(I) (poly)chalcogenide halides, a new class of mixed electron and ion conductors, with the general composition Ag ₁₀Q₄X₃ (Q = chalcogen and X = halogen). A high silver mobility within the polytelluride substructure and a pronounced polymorphism are characteristic features of these solid electrolytes. Phase transition temperatures are reduced upon the substitution of Te by the lighter homologs Se and S. Even low degrees of substitution lead to significantly lower phase transitions for the high-temperature polymorphs compared with Ag ₁₀Te₄Br₃. A permanent disorder within the silver substructure is present for the maximally substituted sulfur containing phases.