Ab initioCalculation of Electric Quadrupole and Magnetic Dipole Transitions in Ions of the N I Isoelectronic Sequence

The electric quadrupole (E2) and magnetic dipole (M1) transitions in the nitrogen isoelectronic sequence ( Z = 10–30) between the levels of the 1s 2 2s 2 2p 3 , 1s 2 2s2p 4 and 1s 2 2p 5 configurations are investigated. The results include wavelengths and radiative E2 and M1 transition probabilities. The stationary second-order many-body perturbation theory (MBPT) was used to account for the electron correlations. A non-local potential was used to calculate the radial part of the effective Hamiltonian. Relativistic corrections were included in the Breit–Pauli approximation. The lowest-order correlation corrections to the one-body part of the spin–orbit interaction operator were also included.