Decomposing Chemical Space: Applications to the Machine Learning of Atomic Energies

Autor: Frederik Ø. Kjeldal, Janus J. Eriksen
Rok vydání: 2023
Předmět:
Zdroj: Journal of Chemical Theory and Computation. 19:2029-2038
ISSN: 1549-9626
1549-9618
DOI: 10.1021/acs.jctc.2c01290
Popis: We apply a number of atomic decomposition schemes across the standard QM7 dataset -- a small model set of organic molecules at equilibrium geometry -- to inspect the possible emergence of trends among contributions to atomization energies from distinct elements embedded within molecules. Specifically, a recent decomposition scheme of ours based on spatially localized molecular orbitals is compared to alternatives that instead partition molecular energies on account of which nuclei individual atomic orbitals are centred on. We find these partitioning schemes to expose the composition of chemical compound space in very dissimilar ways in terms of the grouping, binning, and heterogeneity of discrete atomic contributions, e.g., those associated with hydrogens bonded to different heavy atoms. Furthermore, unphysical dependencies on the one-electron basis set are found for some, but not all of these schemes. The relevance and importance of these compositional factors for training tailored neural network models based on atomic energies are next assessed. We identify both limitations and possible advantages with respect to contemporary machine learning models and discuss the design of potential counterparts based on atoms and the intrinsic energies of these as the principal decomposition units.
21+7 pages, 6 figures. SI as an ancillary file. Version 2: All PhysNet-based results are now based on NN models trained on a combination of atomic and molecular energies (as opposed to only the former in Version 1). SI also updated with a total of four figures
Databáze: OpenAIRE