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Updated: Jul 17, 2026

Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
On the origin of a band gap in compounds of diamond-like structures
Jürgen Köhler1, Shuiquan Deng, Changhoon Lee
1Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany. j.koehler@ fkf.mpg.de
Abstract:
Electronic structure calculations were performed to examine the origin of a band gap present in most 18-electron half-Heusler compounds and its absence in NaTl. In these compounds of diamond-like structures, the presence or absence of a band gap is controlled by the sigma antibonding between the valence s orbitals, and the bonding characteristics of the late-main-group elements depend on the extent of their ns/np hybridization. Implications of these observations on the formal oxidation state and the covalent bonding of the transition-metal atoms in 18-electron half-Heusler and related compounds were discussed.
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