Orbital-Free Density Functional Theory with Continuous Normalizing Flows

TL;DR

This paper introduces a novel orbital-free density functional theory method using continuous normalizing flows to accurately model electronic densities across various molecules, streamlining electronic structure calculations.

Contribution

It proposes a new approach that parameterizes electronic density with normalizing flows, enabling efficient and accurate OF-DFT calculations for diverse chemical systems.

Findings

Successfully replicates electronic densities for diatomic molecules, hydrogen, and water.

Demonstrates the method's applicability across different molecular geometries.

Achieves accurate energy minimization in Cartesian space.

Abstract

Orbital-free density functional theory (OF-DFT) provides an alternative approach for calculating the molecular electronic energy, relying solely on the electron density. In OF-DFT, both the ground-state density is optimized variationally to minimize the total energy functional while satisfying the normalization constraint. In this work, we introduce a novel approach by parameterizing the electronic density with a normalizing flow ansatz, which is also optimized by minimizing the total energy functional. Our model successfully replicates the electronic density for a diverse range of chemical systems, including a one-dimensional diatomic molecule, specifically Lithium hydride with varying interatomic distances, as well as comprehensive simulations of hydrogen and water molecules, all conducted in Cartesian space.