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arXiv · 1702.08576

A Tetrahedron-tiling Method for Crystal Structure Prediction

Qi-Jun Hong·Joseph Yasi·Axel van de Walle
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Abstract

Reliable and robust methods of predicting the crystal structure of a compound, based only on its chemical composition, is crucial to the study of materials and their applications. Despite considerable ongoing research efforts, crystal structure prediction remains a challenging problem that demands large computational resources. Here we propose an efficient approach for first-principles crystal structure prediction. The new method explores and finds crystal structures by tiling together elementary tetrahedra that are energetically favorable and geometrically matching each other. This approach has three distinguishing features: a favorable building unit, an efficient calculation of local energy, and a stochastic Monte Carlo simulation of crystal growth. By applying the method to the crystal structure prediction of various materials, we demonstrate its validity and potential as a promising alternative to current methods.

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Qi-Jun Hong, Joseph Yasi, Axel van de Walle. 2017-02-27. A Tetrahedron-tiling Method for Crystal Structure Prediction. https://doi.org/10.1103/physrevmaterials.1.020801

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