Non-local orbital-free density functional theory incorporating nuclear shell effects

TL;DR

This paper introduces a non-local orbital-free density functional theory for atomic nuclei that successfully incorporates nuclear shell effects, overcoming longstanding challenges and aligning well with exact solutions.

Contribution

The authors develop a non-local orbital-free DFT approach that effectively captures nuclear shell effects using a novel kinetic energy density functional.

Findings

Non-local functional reproduces shell effects accurately.

Nucleon localization function aligns with exact Kohn-Sham results.

Demonstrates feasibility of orbital-free DFT for nuclear structure.

Abstract

Incorporating nuclear shell effects within the framework of orbital-free density functional theory (DFT) has remained a longstanding challenge in nuclear physics. While the Hohenberg-Kohn theorem formally guarantees the existence of an orbital-free density functional that is capable of describing all many-body effects, including shell effects, practical attempts since the 1970s have consistently failed to capture such effects. This persistent difficulty has even led to the misconception that the orbital-free DFT is inherently unable to describe nuclear shell effects. Here we develop a {\it non-local} orbital-free DFT approach for atomic nuclei and demonstrate that nuclear shell effects can be successfully incorporated into the orbital-free DFT through the construction of a non-local kinetic energy density functional. In particular, we show that the non-local orbital-free functional yields a nucleon localization function that, as an established indicator of shell effects, exhibits consistent behavior with the exact Kohn-Sham solution.