Effect of the order-disorder transition on the electronic structure and physical properties of layered cucrs2

Abstract

The work reports a comprehensive study of the Seebeck coefficient, electrical resistivity and heat capacity of CuCrS2 in a wide temperature range of 100–740 K. It was shown that the value of the Seebeck coefficient is significantly affected by the sample treatment procedure. The order-to-disorder (ODT) phase transition was found to cause a metal-insulator transition (MIT). It was established that the ODT diminishes the Seebeck coefficient at high temperatures (T > 700 K). The DFT calculations of the CuCrS2 electronic structure showed that the localization of copper atoms in octa-hedral sites makes the band gap vanish due to the MIT. The decrease of CuCrS2 electrical resistivity in the ODT temperature region corresponds to the MIT.