Machine-learned Laplacian-level density functional from exact exchange-correlation potentials and energies
Abstract
We present NNLap, a machine-learned Laplacian-level exchange-correlation (XC) functional that augments PBE with a neural-network correction depending on the electron density, its gradient, and its Laplacian. The model is trained on exact XC potentials and energies, obtained through inverse density-functional theory (DFT) calculations on configuration-interaction densities. Despite training on only a few systems -- five atoms and three molecules -- the model achieves remarkable accuracy on thermochemistry benchmarks, competing with the meta-GGA functionals SCAN and r2SCAN. It also attains accurate total energies, comparable to SCAN and better than r2SCAN and B3LYP. This shows that a Laplacian-level model, trained on exact XC potentials and energies, can reach the accuracy of meta-GGAs without their orbital dependence.
Related
- Exchange-Correlation Potentials and Energies from Inverse Generalized Kohn-Sham Calculations
- Nonempirical Time-Dependent Density Functional Theory Framework for Nonlocal Exchange--Correlation Potentials
- Influence of exchange–correlation functional on machine-learnt interatomic potentials accuracy: a systematic study in borosilicate glasses
- Influence of Exchange–Correlation Functional on Machine-Learned Interatomic Potentials’ Accuracy: A Systematic Study of Borosilicate Glasses
- Stationarity Constraints Improve Both Energies and Densities of Machine-Learned Exchange-Correlation Functionals
BibTeX
@misc{paul2026machinelearned,
title = {{Machine-learned Laplacian-level density functional from exact exchange-correlation potentials and energies}},
author = {Arghadwip Paul and Bikash Kanungo and Sambit Das and Vikram Gavini},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.34194},
eprint = {2609.34194},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.34194},
}
RIS
TY - UNPB
TI - Machine-learned Laplacian-level density functional from exact exchange-correlation potentials and energies
AU - Arghadwip Paul
AU - Bikash Kanungo
AU - Sambit Das
AU - Vikram Gavini
PY - 2026
DA - 2026/09/28
PB - arXiv
DO - 10.48550/arxiv.2609.34194
UR - https://arxiv.org/abs/2609.34194
AB - We present NNLap, a machine-learned Laplacian-level exchange-correlation (XC) functional that augments PBE with a neural-network correction depending on the electron density, its gradient, and its Laplacian. The model is trained on exact XC potentials and energies, obtained through inverse density-functional theory (DFT) calculations on configuration-interaction densities. Despite training on only a few systems -- five atoms and three molecules -- the model achieves remarkable accuracy on thermochemistry benchmarks, competing with the meta-GGA functionals SCAN and r2SCAN. It also attains accurate total energies, comparable to SCAN and better than r2SCAN and B3LYP. This shows that a Laplacian-level model, trained on exact XC potentials and energies, can reach the accuracy of meta-GGAs without their orbital dependence.
ER -