Dielectric characteristics and phase transitions in Tl(InS2)1 − x(FeSe2)x solid solutions

This paper reports on a study of the electrical conductivity and permittivity of Tl(InS2)1−x(FeSe2)x crystals as functions of composition and temperature. It has been found that the permittivity decreases in magnitude, while the electrical conductivity increases with increasing x. Crystals Tl(InS2)1−x(FeSe2)x have been observed to undergo a sequence of phase transitions characteristic of TlInS2, which manifests itself in formation of anomalies in the σ = f(T) and ɛ = f(T) temperature dependences. It has been shown that as x increases, the phase transition temperatures decrease, while the temperature region within which the incommensurate phase persists broadens slightly.