The studies of the influence of plasma environments on the level structures and transition
properties for highly charged ions are presented. For the relativistic treatment, we
implemented the multiconfiguration Dirac-Fock method incorporating the ion sphere (IS)
model potential, in which the plasma screening is taken into account as a modified
interaction potential between the electron and the nucleus. For the nonrelativistic treatment,
analytical solutions of the Schrödinger equation with two types of the IS screened potential …