Crystal Structure Prediction via Particle Swarm Optimization

TL;DR

This paper introduces a novel crystal structure prediction method using particle swarm optimization (PSO), which efficiently finds stable structures from chemical compositions without relying on traditional genetic algorithms.

Contribution

The paper presents a PSO-based approach with geometric structure factors, variable unit cell sizes, and symmetry constraints, improving efficiency and reliability over existing methods.

Findings

Successfully predicted structures of elemental, binary, and ternary compounds

Achieved high success rate in structure prediction across various bonding types

Reduced computational cost through innovative techniques

Abstract

We have developed a powerful method for crystal structure prediction from "scratch" through particle swarm optimization (PSO) algorithm within the evolutionary scheme. PSO technique is dramatically different with the genetic algorithm and has apparently avoided the use of evolution operators (e.g., crossover and mutation). The approach is based on a highly efficient global minimization of free energy surfaces merging total-energy calculations via PSO technique and requires only chemical compositions for a given compound to predict stable or metastable structures at given external conditions (e.g., pressure). A particularly devised geometrical structure factor method which allows the elimination of similar structures during structure evolution was implemented to enhance the structure search efficiency. The application of designed variable unit cell size technique has greatly reduced the computational cost. Moreover, the symmetry constraint imposed in the structure generation enables the realization of diverse structures, leads to significantly reduced search space and optimization variables, and thus fastens the global structural convergence. The PSO algorithm has been successfully applied to the prediction of many known systems (e.g., elemental, binary and ternary compounds) with various chemical bonding environments (e.g., metallic, ionic, and covalent bonding). The remarkable success rate demonstrates the reliability of this methodology and illustrates the great promise of PSO as a major technique on crystal structure determination.