Differential-Thermal and X-Ray Analysis of TlFeS2 and TlFeSe2 Chalcogenides

Abstract

Triple compounds with the formulas TlFeS₂ and TlFeSe₂ and magnetic properties are investigated via X-ray diffraction, differential-thermal, and thermogravimetric analyses. Their crystal structures are found. It is ascertained that they are described by monoclinic space group C2/m under normal conditions. The atomic coordinates and interatomic distances are determined. From differential-thermal and thermogravimetric analyses performed at temperatures of 30–900°C, it is revealed that stronger covalent bonds are implemented in TlFeS₂ crystals than in TlFeSe₂ compounds. The effects associated with energy exchange in the compounds under study are observed. The physical nature of the observed effects is discussed.