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arXiv · 2107.07683

Finding well-optimized special quasirandom structures with decision diagram

Kohei Shinohara·Atsuto Seko·Takashi Horiyama·Isao Tanaka
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Abstract

The advanced data structure of the zero-suppressed binary decision diagram (ZDD) enables us to efficiently enumerate nonequivalent substitutional structures. Not only can the ZDD store a vast number of structures in a compressed manner, but also can a set of structures satisfying given constraints be extracted from the ZDD efficiently. Here, we present a ZDD-based efficient algorithm for exhaustively searching for special quasirandom structures (SQSs) that mimic the perfectly random substitutional structure. We demonstrate that the current approach can extract only a tiny number of SQSs from a ZDD composed of many substitutional structures (>$10^{12}$). As a result, we find SQSs that are optimized better than those proposed in the literature. A series of SQSs should be helpful for estimating the properties of substitutional solid solutions. Furthermore, the present ZDD-based algorithm should be useful for applying the ZDD to the other structure enumeration problems.

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Kohei Shinohara, Atsuto Seko, Takashi Horiyama, Isao Tanaka. 2021-07-16. Finding well-optimized special quasirandom structures with decision diagram. https://doi.org/10.1103/physrevmaterials.5.113803

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