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arXiv · 1408.3099

On the superconductivity of TiNCl and ZrNCl: A local bonding perspective

Lukas Muechler·Leslie M. Schoop·Claudia Felser
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Abstract

We analyze the superconductors TiNCl and ZrNCl from a local bonding perspective. Although TiNCl crystallizes in an orthorhombic structure and ZrNCl crystallizes in a hexagonal structure, both compounds show significant structural similarities, for example that both consist of layered metal-Nitrogen networks. The local bonding in those two structures is very similar, giving rise to a dispersive conduction band mostly consisting of metal-d -states. Upon doping both compounds show structural changes, which lead to short metal-metal distances, indicating a bonding interaction that might be important for the appearance of superconductivity in these systems. We furthermore draw analogies to other superconductors that are close to a charge density wave instability around a d 1 -configuration and offer a different perspective on this class of superconductors, which show non-BCS-like superconductivity.

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Lukas Muechler, Leslie M. Schoop, Claudia Felser. 2014-08-13. On the superconductivity of TiNCl and ZrNCl: A local bonding perspective. https://arxiv.org/abs/1408.3099

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