arXiv Machine Learning By Joseph Agada, Yishu Wang, Arpan Biswas

CrystalMO-TuRBO: Multi-Objective Trust-Region Bayesian Optimization for High-precision Joint Crystal Structure Refinement

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CrystalMO‑TuRBO is a multi‑objective trust‑region Bayesian optimization framework designed for joint crystal structure refinement using X‑ray and neutron diffraction data. It treats the discrepancies from each modality as separate objectives, first exploring the parameter space globally with parallel Bayesian optimization across multiple scalarizations, then refining locally within a shrinking trust region to achieve high‑precision solutions. Experiments on single‑crystal Ho₂Ti₂O₇ data show that this two‑phase approach improves convergence, robustness, and parameter precision over traditional least‑squares, likelihood‑based, and single‑objective Bayesian methods.

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