Electron diffraction investigation of the AgxTaS2 system. I. Superlattices in Ag1/8TaS2 and Ag2/3TaS2

Abstract

Superlattices are observed by electron diffraction in electrolytically prepared single crystals of stage 1 Ag2/3TaS2 and stage 2 Ag1/3TaS2 intercalation compounds in the temperature region from 300 to 25 K. These superlattice satellites are explained as ordered silver ion superstructures. The silver ions in both compounds undergo an order-disorder transition in two stages. The first occurs near room temperature and leaves about 25% of the silver ions disordered, which in turn order in the second transition near 90 K.