Generalized evolutionary metadynamics for sampling the energy landscapes and its applications

Article

关键词: CRYSTAL-STRUCTURE PREDICTION;    AB-INITIO;    METASTABLE PHASES;    SILICON;    ALLOTROPES;    MINIMA;    BORON;   

DOI  :  10.1103/PhysRevB.92.024106

来源: SCIE

【 摘 要 】

We present an automated scheme to systematically sample energy landscapes of crystalline solids, based on the ideas of metadynamics and evolutionary algorithms. Phase transitions are driven by the evolution of the order parameter (in this case, 6-dimensional order parameters composed of cell vectors components) and aided by atomic displacements corresponding to both zero and nonzero wave vectors, enabling cell size to spontaneously change during simulation. Our technique can be used for efficient prediction of stable crystal structures, and is particularly powerful for mining numerous low-energy configurations and phase transition pathways. By applying this method to boron, we find numerous energetically competitive configurations, based on various packings of B-12 icosahedra. We also observed a low-energy metastable structure of Si(T32) which is likely to be a product of decompression on Si-II. T32 is calculated to have a quasidirect band gap of 1.28 eV, making it promising for photovoltaic applications.

【 授权许可】

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