Dielectronic recombination processes through doubly excited states (4l4l′,4l5l′) in Co-like Pd ions -: art. no. 042705

Ab initio calculations of dielectronic recombination processes from the ground state [Ne core]3s(2)3p(6)3d(9) of Co-like Pd19+ ion through doubly excited states [Ne core]3s(2)3p(6)3d(8)4lnl('), [Ne core]3s(2)3p(5)3d(9)4lnl('), and [Ne core]3s3p(6)3d(9)4lnl(') (n=4 or 5) of Ni-like Pd18+ ions are performed using the multiconfiguration Hartree-Fock method with relativistic correction. Total and state-to-state rate coefficients are obtained in the temperature range from 0.1 to 10(4) eV. Comparison of the rate coefficients from 3s, 3p, and 3d subshell excitations shows 3d subshell excitation dominates over the others in the whole energy region, but 3p and 3s subshell excitation cannot be neglected in high temperature; when electron temperature T>500 eV, the contributions from 3p and 3s subshells are more than 40% and 10% of the dielectronic recombination (DR) rate coefficients from 3d subshell excitations; especially for the DR processes through the doubly excited states n=5, the contribution from 3p subshell excitations is approximately 60% of the rate coefficients from 3d subshell excitations. The two-electron radiative transitions, such as 3d(8)4p4d -> 3d(9)4s and 3d(8)4d(2)-> 3d(9)4p, are found to be important due to the strong configuration interactions, which contribute more than 10% of the total rate coefficients through the doubly excited states [Ne core]3s(2)3p(6)3d(8)4l4l(').