Multiconfiguration Hartree-Fock Results with Breit-Pauli Corrections for Transitions in the Carbon Sequence

The Multiconfiguration Hartree-Fock method, extended to include relativistic effects in the Breit-Pauli approximation (MCHF + BP), has been used to determine wavefunctions for the different LSJ states of the 2 s 2 2 p 2 ground and the 2 s 2 p 3 excited configurations of the carbon iso-electronic sequence for nuclear charges, Z , up to thirty. Term energies and fine-structure splitting have been predicted from these wavefunctions, as well as transition probabilities. The latter include the forbidden transitions, electric quadrupole (E2) and magnetic dipole (M1), between the levels of the ground configuration, as well as the allowed 2 s 2 2 p 2 -2 s 2 p 3 transitions. In this paper our results are reported and typical transitions compared with those from other theories as well as those from observation, as available. For Z up to about 20, our energy levels are generally in better agreement with observation than those from other theories.