XtalOpt Version 14: Variable-Composition Crystal Structure Search for Functional Materials Through Pareto Optimization

Abstract: Version 14 of XtalOpt, evolutionary multi-objective global optimization algorithm for crystal structure prediction, is now available for download from its official website https://xtalopt.github.io. The new version of the code is designed to perform ground state search for novel crystal structures with variable composition by integrating a suite of ab initio methods alongside classical and machine-learning potentials for structural relaxation. The multi-objective search framework has been further enhanced through the introduction of Pareto optimization, enabling efficient discovery of functional materials. Here, we describe the implemented methodologies, provide detailed instructions for their use, and present an overview of additional improvements included in XtalOpt version 14.