Exploration and Optimization in Crystal Structure Prediction: Combining Basin Hopping with Quasi-Random Sampling

We describe the implementation of a Monte Carlo basin hopping global optimization procedure for the prediction of molecular crystal structure. The basin hopping method is combined with quasi-random structure generation in a hybrid method for crystal structure prediction, QR-BH, which combines the low-discrepancy sampling provided by quasi-random sequences with basin hopping's efficiency at locating low energy structures. Through tests on a set of single-component molecular crystals and co-crystals, we demonstrate that QR-BH provides faster location of low energy structures than pure quasi-random sampling, while maintaining the efficient location of higher energy structures that are important for identifying important polymorphs.