{\it Ab initio} studies of electron correlation and Gaunt interaction effects in boron isoelectronic sequence using coupled-cluster theory

TL;DR

This study uses relativistic coupled-cluster theory to analyze electron correlation and Gaunt interaction effects on ionization potentials and hyperfine constants in boron-like ions across Z=8 to 21, providing new hyperfine data.

Contribution

It presents the first comprehensive relativistic coupled-cluster analysis of hyperfine constants and Gaunt effects in boron isoelectronic sequence, including new hyperfine data.

Findings

Gaunt contributions significantly affect ionization potentials and fine structure splitting.

Correlation effects like core polarization are crucial for hyperfine constants.

Most hyperfine constants are reported for the first time within Gaunt limit.

Abstract

In this paper, we have studied electron correlation and Gaunt interaction effects in ionization potentials (IPs) and hyperfine constants A of 2p$^2P_{1/2}$ and 2p$^2P_{3/2}$ states along with the fine structure splitting (FSS) between them for boron isoelectronic sequence using relativistic coupled-cluster (RCC) method. The range of atomic number Z has been taken from 8 to 21. Gaunt contributions are presented at both Dirac-Fock (DF) and coupled-cluster (CC) levels of calculations. The Gaunt corrected correlated results of the IPs and the FSS are compared with the results of NIST. Important correlation contributions like core correlation, core polarisation, pair correlation etc. are studied for hyperfine constants A. Many distinct features of correlation and relativistic effects are observed in these studies. With best of our knowledge, within Gaunt limit, most of the hyperfine constants are presented for the first time in the literature.