Automated Development of Molten Salt Machine Learning Potentials: Application to LiCl.

Autor: Sivaraman G, Guo J, Ward L, Hoyt N, Williamson M, Foster I, Benmore C, Jackson N; Department of Chemistry, University of Illinois, Urbana-Champaign, Urbana, Illinois 61801, United States.
Jazyk: angličtina
Zdroj: The journal of physical chemistry letters [J Phys Chem Lett] 2021 May 06; Vol. 12 (17), pp. 4278-4285. Date of Electronic Publication: 2021 Apr 28.
DOI: 10.1021/acs.jpclett.1c00901
Abstrakt: The in silico modeling of molten salts is critical for emerging "carbon-free" energy applications but is inhibited by the cost of quantum mechanically treating the high polarizabilities of molten salts. Here, we integrate configurational sampling using classical force fields with active learning to automate and accelerate the generation of Gaussian approximation potentials (GAP) for molten salts. This methodology reduces the number of expensive ab initio evaluations required for training set generation to O(100), enabling the facile parametrization of a molten LiCl GAP model that exhibits a 19 000-fold speedup relative to AIMD. The developed molten LiCl GAP model is applied to sample extended spatiotemporal scales, permitting new physical insights into molten LiCl's coordination structure as well as experimentally validated predictions of structures, densities, self-diffusion constants, and ionic conductivities. The developed methodology significantly lowers the barrier to the in silico understanding and design of molten salts across the periodic table.
Databáze: MEDLINE