Electronic Structures and Spectra Properties of Plasma-Embedded Atoms or Ions Under the External Electric-Field

Abstract

A method within the relativistic computational scheme is developed and used to investigate the electronic structures and spectra properties of plasma-embedded atoms/ions placed in an external electric-field by using the configuration interaction approximation, which is proved to be a powerful tool to include both the electron correlation and relativistic effect. In this scheme, the screening potential based on the self-consistent-field ion-sphere model is used to explain the effect of the plasma environment and the weak electric-field is considered as the external perturbation. As a first application, plasma-embedded He$^{+}$ ion is considered as an illustrative case. The influences of the different plasma temperature and density parameters and the external electric field strengths on the energy eigenvalues and transition properties are investigated in detail. Our results indicate that, inclusion of the screening effects destabilizes the atomic system (decreases energy eigenvalues and transition properties), whereas inclusion of the external electric field counteracts these effects by lowering the energies of the embedded case, thereby improving the stability of atomic system. Overall, compared to the electric field effect on the electronic structures and spectra properties of a guest ion, an obvious deflection takes place for the plasma screening, which implies that the latter has stronger effects. The present results are consistent with the results of the other available theoretical simulations.