Excitation Energies, Oscillator Strengths and Lifetimes in Doubly Ionised Phosphorus

Abstract

We have calculated the excitation energies, oscillator strengths and transition probabilities for electric-dipole-allowed and inter-combination transitions among the lowest 25 LS levels belonging to the configurations (1s22s22p6)3s23p(2Po), 3s3p2(2S, 2P, 2D, 4P), 3s23d(2D), 3p3(4So, 2Po, 2Do), 3s3p(3Po)3d(2Po, 2Do, 2Fo, 4Po, 4Do, 4Fo), 3s3p(1Po)3d(2Po, 2Do, 2Fo), 3s24s(2S), 3s24p(2Po), 3s24d(2D), 3s24f(2Fo), 3s3p(3Po)4s(2Po, 4Po), and 3s3p(1Po)4s(2Po) of P III using the Program CIV3 of Hibbert. These states are represented by extensive configuration-interaction (CI) wave functions. The radiative lifetimes of 18 doublet and 4 quartet states of P III have also been calculated from our transition probabilities. Our results are compared with experimental and other theoretical data. To assess the importance of relativistic effects on our calculated values, we have carried out calculations in the intermediate-coupling scheme using the Breit-Pauli Hamiltonian. Small adjustments to the diagonal elements of the Hamiltonian matrices have been made. The energy splittings of 54 fine-structure levels, the oscillator strengths and transition probabilities for some strong dipole-allowed and intercombination transitions and the lifetimes of some fine-structure levels are presented.