Effect of the Order-Disorder Transition on the Electronic Structure and Physical Properties of Layered CuCrS2

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 octahedral 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.

Automated summary

The study comprehensively investigates the Seebeck coefficient of CuCrS2 in a wide temperature range, showing significant impacts of sample treatment on the value. It also reveals that the order-to-disorder phase transition induces a metal-insulator transition and reduces the Seebeck coefficient at high temperatures. Additionally, DFT calculations demonstrate the localization of copper atoms in octahedral sites, leading to a band gap vanishing due to the MIT in CuCrS2.