The low-temperature (80–190 K) thermoelectric power of TlCrS2 has been shown to follow the relation α(T) = (0.2T – 13) μV/K, characteristic of charge transport through localized states in the band gap. As the temperature is raised from 338 to 370 K, where the electrical conductivity is dominated by charge carriers excited to the allowed band, the thermoelectric power varies of TlCrS2 is inversely proportional to temperature. The temperature coefficient of the activation energy for conduction in TlCrS2 is γ = 2.06 × 10–4 eV/K. We have determined parameters of localized states in TlCrS2.

We have determined the density of localized states near the Fermi level in TlCrS2: NF = 8.2 × 1019 eV–1 cm–3. The calculated average hop distance in TlCrS2 is 60 Å, and the energy spread of trap states near the Fermi level is ΔE = 0.027 eV. This value of ΔE agrees with the estimated average activation energy for hopping in TlCrS2, which has been determined to be ΔW = 0.026 eV. The estimated concentration of localizes states in the bandgap of TlCrS2 is Nt = 2.2 × 1018 cm–3.

"Hopping Thermoelectric Power in TlCrS2" S. N. Mustafaeva, S. M. Asadov, and A. I. Jabbarova, Inorganic Materials, 2020, Vol. 56, No. 4, pp. 333–337.