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Efficient Generation of Permutationally Invariant Potential Energy Surfaces for Large Molecules.

ABSTRACT: An efficient method is described for generating a fragmented, permutationally invariant polynomial basis to fit electronic energies and, if available, gradients for large molecules. The method presented rests on the fragmentation of a large molecule into any number of fragments while maintaining the permutational invariance and uniqueness of the polynomials. The new approach improves on a previous one reported by Qu and Bowman by avoiding repetition of polynomials in the fitting basis set and speeding up gradient evaluations while keeping the accuracy of the PES. The method is demonstrated for CH₃-NH-CO-CH₃ (N-methylacetamide) and NH₂-CH₂-COOH (glycine).

SUBMITTER: Conte R

PROVIDER: S-EPMC7997398 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Efficient Generation of Permutationally Invariant Potential Energy Surfaces for Large Molecules.

Conte Riccardo R Qu Chen C Houston Paul L PL Bowman Joel M JM

Journal of chemical theory and computation 20200408 5

An efficient method is described for generating a fragmented, permutationally invariant polynomial basis to fit electronic energies and, if available, gradients for large molecules. The method presented rests on the fragmentation of a large molecule into any number of fragments while maintaining the permutational invariance and uniqueness of the polynomials. The new approach improves on a previous one reported by Qu and Bowman by avoiding repetition of polynomials in the fitting basis set and sp ...[more]

PMID: 32212729

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