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arXiv · 2503.22596

Global structure searches under varying temperatures and pressures using polynomial machine learning potentials: A case study on silicon

Hayato Wakai·Atsuto Seko·Isao Tanaka
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Abstract

Polynomial machine learning potentials (MLPs) based on polynomial rotational invariants have been systematically developed for various systems and applied to efficiently predict crystal structures. In this study, we propose a robust methodology founded on polynomial MLPs to comprehensively enumerate crystal structures under high-pressure conditions and to evaluate their phase stability at finite temperatures. The proposed approach involves constructing polynomial MLPs with high predictive accuracy across a broad range of pressures, conducting reliable global structure searches, and performing exhaustive self-consistent phonon calculations. We demonstrate the effectiveness of this approach by examining elemental silicon at pressures up to 100 GPa and temperatures up to 1000 K, revealing stable phases across these conditions. The framework established in this study offers a powerful strategy for predicting crystal structures and phase stability under high-pressure and finite-temperature conditions.

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Hayato Wakai, Atsuto Seko, Isao Tanaka. 2025-03-28. Global structure searches under varying temperatures and pressures using polynomial machine learning potentials: A case study on silicon. https://arxiv.org/abs/2503.22596

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