We wish to describe a potential energy surface by using a basis of permutationally invariant polynomials whose coefficients will be determined by numerical regression so as to smoothly fit a dataset of electronic energies as well as, perhaps, gradients. The polynomials will be powers of transformed internuclear distances, usually either Morse variables, exp(−ri,j/λ), where λ is a constant range hyperparameter, or reciprocals of the distances, 1/ri,j. The question we address is how to create the most efficient basis, including (a) which polynomials to keep or discard, (b) how many polynomials will be needed, (c) how to make sure the polynomials correctly reproduce the zero interaction at a large distance, (d) how to ensure special symmetries, and (e) how to calculate gradients efficiently. This article discusses how these questions can be answered by using a set of programs to choose and manipulate the polynomials as well as to write efficient Fortran programs for the calculation of energies and gradients. A user-friendly interface for access to monomial symmetrization approach results is also described. The software for these programs is now publicly available.

PESPIP: Software to Fit Complex Molecular and Many-body Potential Energy Surfaces with Permutationally Invariant Polynomials / P.L. Houston, C. Qu, Q. Yu, R. Conte, A. Nandi, J.K. Li, J.M. Bowman. - In: THE JOURNAL OF CHEMICAL PHYSICS. - ISSN 0021-9606. - 158:4(2023), pp. 044109.1-044109.14. [10.1063/5.0134442]

PESPIP: Software to Fit Complex Molecular and Many-body Potential Energy Surfaces with Permutationally Invariant Polynomials

R. Conte
;
2023

Abstract

We wish to describe a potential energy surface by using a basis of permutationally invariant polynomials whose coefficients will be determined by numerical regression so as to smoothly fit a dataset of electronic energies as well as, perhaps, gradients. The polynomials will be powers of transformed internuclear distances, usually either Morse variables, exp(−ri,j/λ), where λ is a constant range hyperparameter, or reciprocals of the distances, 1/ri,j. The question we address is how to create the most efficient basis, including (a) which polynomials to keep or discard, (b) how many polynomials will be needed, (c) how to make sure the polynomials correctly reproduce the zero interaction at a large distance, (d) how to ensure special symmetries, and (e) how to calculate gradients efficiently. This article discusses how these questions can be answered by using a set of programs to choose and manipulate the polynomials as well as to write efficient Fortran programs for the calculation of energies and gradients. A user-friendly interface for access to monomial symmetrization approach results is also described. The software for these programs is now publicly available.
Settore CHIM/02 - Chimica Fisica
2023
Article (author)
File in questo prodotto:
File Dimensione Formato  
PESPIP.pdf

accesso riservato

Tipologia: Publisher's version/PDF
Dimensione 5.35 MB
Formato Adobe PDF
5.35 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
PlayingWithPIPsJCTC_II.pdf

accesso riservato

Tipologia: Post-print, accepted manuscript ecc. (versione accettata dall'editore)
Dimensione 886.35 kB
Formato Adobe PDF
886.35 kB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/952317
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? ND
social impact