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arXiv · 1107.4300

First Principles Phase Diagram Calculations for the Octahedral-Interstitial System ZrO$_{X}$, $0 \leq X \leq 1/2$

Benjamin P. Burton·Axel van de Walle·Harold T. Stokes
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Abstract

First principles based phase diagram calculations were performed for the octahedral-interstitial solid solution system αZrOX (αZr[ ]_(1-X)OX; [ ]=Vacancy; 0 \leq X \leq 1/2). The cluster expansion method was used to do a ground state analysis, and to calculate the phase diagram. The predicted diagram has four ordered ground-states in the range 0 \leq X \leq 1/2, but one of these, at X=5/12, is predicted to disproportionate at T \approx 20K, well below the experimentally investigated range T \approx 420K. Thus, at T \succeq 420K, the first-principles based calculation predicts three ordered phases rather than the four that have been reported by experimentalists.

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Benjamin P. Burton, Axel van de Walle, Harold T. Stokes. 2011-07-21. First Principles Phase Diagram Calculations for the Octahedral-Interstitial System ZrO$_{X}$, $0 \leq X \leq 1/2$. https://doi.org/10.1143/jpsj.81.014004

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