  The broadening of lines by Stark effect is widely used for inferring electron
density and temperature in plasmas. Stark-effect calculations often rely on
atomic data (transition rates, energy levels,...) not always exhaustive and/or
valid only for isolated atoms. In this work, we first present a recent
development in the detailed opacity code SCO-RCG for K-shell spectroscopy. The
approach is adapted from the work of Gilles and Peyrusse. Neglecting
non-diagonal terms in dipolar and collision operators, the line profile is
expressed as a sum of Voigt functions associated to the Stark components. The
formalism relies on the use of parabolic coordinates and the relativistic
fine-structure of Lyman lines is included by diagonalizing the hamiltonian
matrix associated to quantum states having the same principal quantum number n.
The SCO-RCG code enables one to investigate plasma environment effects, the
impact of the microfield distribution, the decoupling between electron and ion
temperatures and the role of satellite lines (such as Li-like 1s nl n'l' - 1s2
nl, Be-like, etc.). Atomic-structure calculations have reached levels of
accuracy which require evaluation of Breit interaction and many-electron
quantum electro-dynamics (QED) contributions. Although much work was done for
QED effects (self-energy and vacuum polarization) in hydrogenic atoms, the case
of an arbitrary number of electrons is more complicated. Since exact analytic
solutions do not exist, a number of heuristic methods have been used to
approximate the screening of additional \'electrons in the self-energy part. We
compare different ways of including such effects in atomic-structure codes
(Slater-Condon, Multi-Configuration Dirac-Fock, etc.).
