Investigation on the structure and

Investigation on the structure and dynamics of atomic systems embedded in plasma screening environments has attracted considerable interest in recent years due to their great importance in modeling the plasma thermodynamic properties such as internal energy and pressure, and simulating elementary atomic processes in plasmas, e.g. ionization balance, opacity, and radiative and collisional transitions [1–4]. Due to the enormous variation of plasma conditions characterized by temperature and mean number of density, several simplified models have been proposed to efficiently and effectively simulate the quasi-static fields in plasmas. The Debye–Hückel or Yukawa model [5] is the most successful approach to describe the weakly-coupled classical plasmas where the electrostatic potential for the test atom placed in an otherwise uniform, neutral plasma is expressed as an exponential screened Coulomb potential, V(r) = −r , in which the screening parameter λ is the reciprocal of Debye length [1]. In the past few years, there have been considerable amount of investigations on the variation of energy levels for neutral or ionized atoms within Debye–Hückel model (see the reviews of Refs. [3,4] and references therein). These calculations, however, limits their applicability to low-density and high-temperature plasmas.