Determining nanoparticle structures using FANTASTX

Determining the atomistic structures of nanoparticles is a fundamental problem. Their structures determine their functionality, and therefore their effectiveness in applications. Although there are both experimental and computational methods to determine these nanoscale structures, they both possess limitations. We develop FANTASTX (Fully Automated Nanoscale To Atomistic Structure from Theory and eXperiment) to overcome the limitations of either by combining both experimental and computational data. We demonstrate the effectiveness of FANTASTX by determining the structures of Au and IrO_x nanoparticles from x-ray pair distribution function (PDF) data and density functional theory (DFT) calculations, using multi-objective optimization and a variety of canonical and grand canonical sampling algorithms.