Relativistic ab initio spectroscopy study of forbidden lines of singly ionized zinc

Abstract

The ab initio calculation has been carried out to study the astrophysically important forbidden electromagnetic transition rates of singly ionized zinc (Zn II). Electron correlations are considered to all orders using coupled-cluster theory in the relativistic framework. Calculated excitation energies are in excellent agreement with the experimental values, wherever available. Forbidden transition rates due to the magnetic dipole and electric quadrupole transitions are estimated for the first time in the literature, to our knowledge. These transitions span the range of ultraviolet, visible and near infrared regions, and are crucial for astrophysical observations.