Electrical conductivity and composition range of Ag2HgI4 between room temperature and 75°C

Abstract The composition range of α- and β-Ag 2 HgI 4 near the transformation temperature is determined by X-ray diffraction. The electrical conductivity measured in the α-phase is nearly unaffected by deviation from stoichiometry. This is caused by a compensation of the composition dependences of σ 0 and of the activation energy E A . From the experimental results the dependences of the entropy and of the Gibbs energy for migration of Ag-ions on temperature and on composition are estimated.