Anionic character of the conduction band of sodium chloride.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35190545.
- Also identified by DOI 10.1038/s41467-022-28392-8 and PMC identifier 8861091.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The alkali halides are ionic compounds. Each alkali atom donates an electron to a halogen atom, leading to ions with full shells. The valence band is mainly located on halogen atoms, while, in a traditional picture, the conduction band is mainly located on alkali atoms. Scanning tunnelling microscopy of NaCl at 4 K actually shows that the conduction band is located on Cl- because the strong Madelung potential reverses the order of the Na+ 3s and Cl- 4s levels. We verify this reversal is true for both atomically thin and bulk NaCl, and discuss implications for II-VI and I-VII compounds.