Relativistic configuration-interaction calculations of energy levels of the $1s^{2}2l$ and $1s2l2l^{\prime }$ states in lithium-like ions: carbon through chlorine

Abstract

We present systematic calculations of energy levels of the $1s^{2}2l$ and $1s2l2l^{\prime }$ states of ions along the lithium isoelectronic sequence from carbon till chlorine. The calculations are performed by using the relativistic-configuration-interaction method adapted to the treatment of autoionizing core-excited states. The relativistic energies are supplemented with the QED energy shifts calculated within the model QED operator approach. A systematic estimation of the theoretical uncertainties is performed for every electronic state and every nuclear charge. The results are in agreement with existing high-precision theoretical and experimental data for the ground and first excited states. For the core-excited states, our theory is much more accurate than the presently available measurements.

Table IV is corrected according to erratum [Phys. Rev. A 96, 069901(E) (2017)]