DSC and EPR investigations of structural phase transitions in thallium indium disulphide single crystals

The results of Differential Scanning Calorimetry (DSC) and Electron Paramagnetic Resonance (EPR) investigations of TlInS2 single crystal in the temperature range of structural phase transitions are presented. The temperature dependence of the heat capacity C-p (T) has been obtained using DSC as a new technique applied to this crystal and relevant anomalies of C-p (T) at the temperatures of the phase transitions have been revealed. These anomalies are in accordance with obtained significant changes in EPR spectra, associated with strong splitting existing resonance lines and appearance of additional lines at the temperatures of the phase transitions below 200 K. The results are discussed in comparison with earlier reported data on structural transformations in TlInS2.