Electronic properties and band structure of IrSe 2

Abstract

Transport coefficient measurements (DC conductivity and thermoelectric power) were performed on compacted bars of polycrystalline IrSe 2 in the 100–570 K temperature range. The experimental results are interpeted on the basis of an n-type compensated semiconductor model. At low temperatures, a narrow band which originates from non-stoichiometry mainly participates in the conduction by thermally activated hopping of small polarons. The charge balance adopted by anionic groups is discussed. The schematic band model which is retained takes into account all the transport properties and the ion charge balance Ir 3+Se 2-(Se 2) 2- 1/ 2. Moreover, IrSe 2 has recently been shown to function as a cathode material in lithium batteries.