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arXiv · 2410.14013

Phase stability in the Hf-N and Zr-N systems

Jonathan Li·Derick Ober·Anton Van der Ven
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Abstract

Hf and Zr nitrides are promising compounds for many technologically important areas, including high temperature structural applications, quantum computing and solar/optical applications. This article reports on a comprehensive first-principles statistical mechanics study of phase stability in the Hf-N and Zr-N binary systems. A high solubility of nitrogen in the hcp forms of Hf and Zr is predicted. The rocksalt forms of HfN and ZrN can also tolerate a high degree of off-stoichiometry through the introduction of nitrogen and metal vacancies. The Hf-N binary favors a family of stacking faulted parent crystal structures at intermediate nitrogen concentrations that host a unique form of short-range order among nitrogen interstitials and vacancies. These phases can accommodate some degree of configurational entropy and remain ordered to temperatures as high as 1200K.

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Jonathan Li, Derick Ober, Anton Van der Ven. 2024-10-17. Phase stability in the Hf-N and Zr-N systems. https://doi.org/10.1103/physrevmaterials.8.123603

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