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Context.We aim to present a comprehensive theoretical investigation of dielectronic recombination (DR) of the silicon-like isoelectronic sequence and provide DR and radiative recombination (RR) data that can be used within a generalized collisional-radiative modelling framework.Aims.Total and final-state level-resolved DR and RR rate coefficients for the ground and metastable initial levels of 16 ions between P+and Zn16+are determined.Methods.We carried out multi-configurational Breit-Pauli DR calculations for silicon-like ions in the independent processes, isolated resonance, distorted wave approximation. Both Δnc= 0 and Δnc= 1 core excitations are included usingLSand intermediate coupling schemes.Results.Results are presented for a selected number of ions and compared to all other existing theoretical and experimental data. The total dielectronic and radiative recombination rate coefficients for the ground state are presented in tabulated form for easy implementation into spectral modelling codes. These data can also be accessed from the Atomic Data and Analysis Structure (ADAS) OPEN-ADAS database. This work is a part of an assembly of a dielectronic recombination database for the modelling of dynamic finite-density plasmas.

Partial and total dielectronic recombination (DR) rate coefficients for fluorine- like ions forming neon-like systems have been calculated as part of the assembly of a final-state level-resolved DR database necessary for the modelling of dynamic finite-density plasmas (Badnell et al. 2003). Calculations have been performed for DR of both ground and metastable initial states for Ne+ to Zn21+, as well as for Kr27+, Mo33+, and Xe45+. Results for a selection of ions are presented and discussed. We find that low-temperature DR, via 2 -> 2 core excitations involving no change in the principal quantum number of the core electron, does not scale smoothly with nuclear charge Z due to resonances straddling the ionization limit of the recombined system, thereby making explicit calculations for each ion necessary. Most of the earlier calculations neglected contributions from the fine-structure 2p(3/2)-2p(1/2) excitation which has been shown to be very important for low-temperature DR coefficients. The DR data are suitable for modelling of solar and cosmic plasmas under conditions of collisional ionization equilibrium, photoionization equilibrium, and non-equilibrium ionization.

Dielectronic recombination (DR) and radiative recombination (RR) data for neon-like ions forming sodium-like systems has been calculated as part of the assembly of a DR database necessary for modelling of dynamic and/or finite-density plasmas (Badnell et al. 2003). Dielectronic recombination coefficients for neon-like ions from Na + to Zn 20+ , as well as Kr 26+ , Mo 32+ , Cd 38+ , and Xe 44+ , are presented and the results discussed.

Dielectronic recombination (DR) and radiative recombination (RR) data for carbon-like ions forming nitrogen-like ions have been calculated as part of the assembly of a level-resolved DR and RR database necessary for modelling of dynamic finite-density plasmas (Badnell et al. 2003). Total DR and RR rate coefficients are presented and the results discussed for N + to Zn 24+ ,a s well as Kr 30+ ,M o 36+ ,C d 42+ ,a nd Xe 48+ . We find that the 2 → 2 (no change in the principal quantum number of the core electron) low-temperature DR does not scale smoothly with nuclear charge Z due to resonances straddling the ionization limit, thereby making explicit calculations for each ion necessary. The RR and DR data are suitable for modelling of solar and cosmic plasmas under conditions of collisional ionization equilibrium, photoionization equilibrium, and non-equilibrium ionization.

Context. A comprehensive study of dielectronic recombination (DR) for the aluminum-like isoelectronic sequence has been completed. Aims. Total and final-state resolved DR rate coefficients for the ground and metastable initial levels of 17 ions between Si ii and Zn xviii are presented. Methods. Within an isolated-resonance, distorted-wave (IPIRDW) approximation, multiconfiguration Breit-Pauli (MCBP) calculations are carried out for the total and partial DR rate coefficients of Al-like ions. Both Δnc = 0 and Δnc = 1 core-excitations are included, using LS-coupled and intermediate-coupling (IC) schemes. Results. The inaccuracies of earlier empirical data and/or LS-coupling calculations, particularly at lower temperatures characteristic of photoionized plasmas, is demonstrated by comparison with present, state-of-the-art IC DR rate coefficients. Fine-structure effects are found to increase the DR rate coefficient at low temperatures and decrease it at high temperatures, rendering earlier LS calculations incomplete. Good agreement is found between present IC results and experimental measurements.