Valence Bands of the Cu—III—VI2 Chalcopyrites Studied by Photoemission Spectra, X‐Ray Emission Spectra, and Electronic Structure Calculations

Ultraviolet and X‐ray excited photoemission spectra and Cu Kβ5 X‐ray emission spectra are used to measure the valence band density of states in CuGaTe2 and CuInTe2. In both compounds the density of states exhibits five structures which are ascribed to Cu 3d—Te 5p hybridized states, Ga 4s/In 5s—Te 5p bonding states, and Te 5s states. The valence band density of states of all Ga‐and In‐containing Cu—III—VI2 is calculated in an atomic orbital basis with the noble metal d states explicitly included. The agreement between theory and experiment is good for CuGaTe2 and except the In 5s—VI p bonding states also for the CuInVI2 chalcopyrites. Larger discrepancies between theory and experiment are found for CuGaS2 and CuGaSe2.