Crystal Structures and Electronic Properties of BaAu Compound under High Pressure
Bingtan Li1, Jianyun Wang1, Shuai Sun2
1State Key Laboratory of Superhard Materials, International Center of Computational Method & Software, College of Physics, Jilin University, Changchun 130012, China.
Abstract:
The investigations of Au-bearing alloy materials have been of broad research interest as their relevant features exhibit significant advantages compared with pure Au. Here, we extensively investigate the compression behaviors of BaAu compounds via first-principles calculations and find that a high-pressure cubic phase is calculated to be stable above 12 GPa. Further electronic calculations indicate that despite the low electronegativity of Ba, Fd-3m-structured BaAu exhibits metallic characteristics, which is different from those of semiconducting alkali metal aurides that possess slight characteristics of an ionic compound. These findings provide a step toward a further understanding of the electronic properties of BaAu compounds and provide key insight for exploring the other Au-bearing alloy materials under extreme conditions.
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