Crystal Structure of the Solid Electrolyte, RbAg 4 I 5

Abstract

The crystal structure of the solid electrolyte RbAg₄I₅ has been determined from single-crystal x-ray diffraction counter data. There are four RbAg₄I₅ in a cubic unit cell with a = 11.24 Å. The structure refinement, by least squares, is based on space group P4₁3 (O⁷). The arrangement of the iodide ions is similar to that of the manganese atoms in β-manganese, and provides 56 iodide tetrahedra per unit cell, which share faces in such manner as to provide diffusion paths for the silver ions. The occurrence of the two low-temperature phases of RbAg₄I₅ has been established by x-ray diffraction and optical examination.