Saved in:
Bibliographic Details
Main Authors: Mitchell, Michael A. J., Ferrandis, Teresa Del Aguila, Sanvito, Stefano
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2412.08143
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866929624522424320
author Mitchell, Michael A. J.
Ferrandis, Teresa Del Aguila
Sanvito, Stefano
author_facet Mitchell, Michael A. J.
Ferrandis, Teresa Del Aguila
Sanvito, Stefano
contents Orbital-free density functional theory promises to deliver linear-scaling electronic structure calculations. This requires the knowledge of the non-interacting kinetic-energy density functional (KEDF), which should be accurate and must admit accurate functional derivatives, so that a minimization procedure can be designed. In this work, symbolic regression is explored as an alternative means to machine-learn the KEDF, which results into analytical expressions, whose functional derivatives are easy to compute. The so-determined semi-local functional forms are investigated as a function of the electron number, and we are able to track the transition from the von Weizsäcker functional, exact for the one-electron case, to the Thomas-Fermi functional, exact in the homogeneous electron gas limit. A number of separate searches are performed, ranging from totally unconstrained to constrained in the form of an enhancement factor. This work highlights the complexity in constructing semi-local approximations of the KEDF and the potential of symbolic regression to advance the search.
format Preprint
id arxiv_https___arxiv_org_abs_2412_08143
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle 1D Kinetic Energy Density Functionals learned with Symbolic Regression
Mitchell, Michael A. J.
Ferrandis, Teresa Del Aguila
Sanvito, Stefano
Materials Science
Orbital-free density functional theory promises to deliver linear-scaling electronic structure calculations. This requires the knowledge of the non-interacting kinetic-energy density functional (KEDF), which should be accurate and must admit accurate functional derivatives, so that a minimization procedure can be designed. In this work, symbolic regression is explored as an alternative means to machine-learn the KEDF, which results into analytical expressions, whose functional derivatives are easy to compute. The so-determined semi-local functional forms are investigated as a function of the electron number, and we are able to track the transition from the von Weizsäcker functional, exact for the one-electron case, to the Thomas-Fermi functional, exact in the homogeneous electron gas limit. A number of separate searches are performed, ranging from totally unconstrained to constrained in the form of an enhancement factor. This work highlights the complexity in constructing semi-local approximations of the KEDF and the potential of symbolic regression to advance the search.
title 1D Kinetic Energy Density Functionals learned with Symbolic Regression
topic Materials Science
url https://arxiv.org/abs/2412.08143