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arXiv · 2310.14070

Anionic Character of the Conduction Band of Sodium Chloride

Christopher C. Leon·Abhishek Grewal·Klaus Kuhnke·Klaus Kern·Olle Gunnarsson
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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.

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Christopher C. Leon, Abhishek Grewal, Klaus Kuhnke, Klaus Kern, Olle Gunnarsson. 2023-10-21. Anionic Character of the Conduction Band of Sodium Chloride. https://doi.org/10.1038/s41467-022-28392-8

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