Features of incommensurate phases in crystals TlGaSe2 and TlInS2

TL;DR

This paper investigates the phase transition sequence in layered crystals TlGaSe2 and TlInS2, deriving the dielectric constant's temperature dependence and comparing theoretical results with experimental data.

Contribution

It introduces a theoretical model for incommensurate phase transitions in layered crystals and compares predictions with experimental observations.

Findings

Derived temperature dependence of dielectric constant

Identified sequence of phase transitions in layered crystals

Compared theoretical results with experimental data

Abstract

The theory of a sequence of phase transitions of high-symmetry-incommensurate-commensurate phase controlled by competing order parameters is investigated. The temperature dependence of dielectric constant is derived. The comparison of the obtained results with experimental data for layered crystals is discussed.