Diamagnetic susceptibility of neon and argon including leading relativistic effects

TL;DR

This paper presents highly accurate theoretical calculations of the diamagnetic susceptibility of neon and argon atoms, incorporating relativistic and QED effects to improve precision over previous models.

Contribution

It introduces a comprehensive relativistic and QED correction framework for calculating atomic diamagnetic susceptibilities using coupled-cluster methods.

Findings

Calculated susceptibilities: neon -8.4786(7)×10^{-5} a_0^3, argon -22.9545(32)×10^{-5} a_0^3

Relativistic and QED effects significantly refine susceptibility estimates

Small corrections from nuclear mass and size were confirmed.

Abstract

We report theoretical calculations of the static diamagnetic susceptibility, $\chi_0$, of neon and argon atoms. The calculations were performed using a hierarchy coupled-cluster methods combined with application of both the Gaussian and Slater orbital basis sets. We included the complete relativistic correction of order of $\alpha^4$, where $\alpha$ is the fine structure constant, and obtained an estimate of the quantum electrodynamics (QED) contributions. The finite nuclear mass and size corrections were also considered but are found to be small. The final results are $\chi_0=-8.4786(7)\cdot10^{-5}$ $a_0^3$ for the neon and $\chi_0=-22.9545(32)\cdot10^{-5}$ $a_0^3$ for the argon atom, where $a_0$ is the Bohr radius. The uncertainties in the last digits, shown in the parentheses, are primarily due to the errors in the non-relativistic electronic wavefunction, as well as due to the neglected quantum electrodynamics corrections.