Spectral/structural data of helium atoms with exponential-cosine-screened coulomb potentials

Abstract

Atomic systems with exponential-cosine-screened Coulomb (ECSC) or static screened Coulomb (SSC) potentials have drawn considerable attention recently due to the possible applications to atoms in plasma environments. In this work, we develop a computing scheme to deal with the electron-electron correlation terms with the screened Coulomb interactions instead of the conventional expansion method using the Gegenbauer's addition theorem. Based on this approach, we investigate the helium atom with the ECSC potentials. Bypassing the complex expansion functions for electron-electron interactions, the proposed approach simplifies the calculations greatly and provides an advantage on programming. The results are found to be in good agreement with the existing data. Bound-state energies, oscillator strengths, and multipole polarizabilities varying with the screening parameters are presented. Comparisons of the ECSC potentials are made with the SSC potentials. The influence of screening effect on the energies, oscillator strengths, and polarizabilities is discussed.