Author(s): Yu, HY (Yu, Haoyang); Cai, XF (Cai, Xuefen); Yang, Y (Yang, Yang); Wang, ZH (Wang, Zhi-Hao); Wei, SH (Wei, Su-Huai)

Source: COMPUTATIONAL MATERIALS SCIENCE Volume: 203 Article Number: 111157 DOI: 10.1016/j.commatsci.2021.111157 Published: FEB 15 2022

Abstract: Unlike the conventional zinc-blende II-VI and III-V common-cation systems, which exhibit a general trend of decreasing band gap with increasing anion atomic number, the zinc-blende I-VII cuprous halides CuX (X = Cl, Br, and I) all have an approximately equal direct band gap. Here, using first-principles calculations, we demonstrate that this band gap anomaly in Cu halides is attributed to the unique energy level order of Cu 3d well above X p, making the valence band maximum (VBM) an antibonding state derived mostly from the Cu 3d orbital, thus, a relatively small variation of the band gap with respect to the anion atomic number.

Accession Number: WOS:000744047700002

ISSN: 0927-0256

eISSN: 1879-0801

Full Text: https://www.sciencedirect.com/science/article/pii/S0927025621008156?via%3Dihub