DIELECTRONIC RECOMBINATION OF NI-LIKE IONS THROUGH THE 3D(9)4LN'L' (N'=4,5) CU-LIKE CONFIGURATIONS

Ab initio calculations of the rate coefficients for dielectronic recom bination (DR) of ten ions along the Ni I isoelectronic sequence in the ground state (Mo14+, Ag19+, Xe26+, Pr31+, Gd36+, Dy38+, Ta45+, Au51At57+, and U64+) through the Cu-like 3d(9)4ln'l' (n'=4,5) inner-shell excited configurations were performed using the HULLAC code package. R esonant and nonresonant radiative stabilizing transitions and decays t o autoionizing levels followed by radiative cascades are included. Col lisional transitions following electron capture are neglected. Nonreso nant stabilizing transitions are found to enhance the DR rates, and ma y even dominate the process at low electron temperature. The remarkabl e difference between the isoelectronic trend of the rate coefficients for DR through 3d(9)4l4l' and through 3d(9)4/5l' is emphasized. The tr end of DR through 3d(9)4l4l' shows irregularities at relatively low te mperature due to the progressive closing of DR channels as Z increases . Thus, the DR coefficients cannot be reproduced or interpolated by a simple analytical formula. Even for the smooth contributions of the 3d (9)4l5l' configurations, a simplified model using configuration averag ing for autoionization and radiative decays instead of level-by-level detailed computations is found to overestimate the DR rates by a facto r of up to 2.