First-principles band-structure calculations and X-ray photoelectron spectroscopy studies of the electronic structure of TlPb2Cl5

[Display omitted] •Electronic structure of TlPb2Cl5 is calculated by the FP-LAPW method.•The valence band is dominated by contributions of Cl 3p states.•Contributions of Pb 6p* states dominate at the bottom of the conduction band.•The FP-LAPW data allow concluding that TlPb2Cl5 is an indirect-gap material.•XPS core-level and valence-band spectra of polycrystalline TlPb2Cl5 are measured. We report on first-principles calculations of total and partial densities of states of atoms constituting TlPb2Cl5 using the full potential linearized augmented plane wave (FP-LAPW) method. The calculations reveal that the valence band of TlPb2Cl5 is dominated by contributions of the Cl 3p-like states, which contribute mainly at the top of the valence band with also significant contributions throughout the whole valence-band region. In addition, the bottom of the conduction band of TlPb2Cl5 is composed mainly of contributions of the unoccupied Pb 6p-like states. Our FP-LAPW data indicate that the TlPb2Cl5 compound is an indirect-gap material with band gap of 3.42eV. The X-ray photoelectron core-level and valence-band spectra for pristine and Ar+ ion-irradiated surfaces of a TlPb2Cl5 polycrystalline sample were measured. The measurements reveal high chemical stability and confirm experimentally the low hygroscopicity of TlPb2Cl5 surface.