Revised and extended analysis of the third spectrum of silver: Ag III

The spectrum of doubly ionized silver (Ag III) having the ground configuration 4p(6)4d(9) has been investigated. The silver spectra were recorded on a 3-m normal incidence vacuum spectrograph at St. Francis Xavier University, Antigonish (Canada) using a triggered spark source. Theoretical predictions based on the Hartree-Fock method were made using superposition of interacting configurations and relativistic corrections. For proper interpretation of configuration interaction, the configurations 4p(6)[4d(9), 4d(8)ns (n=5-9), 4d(8)nd (n=5-9), 4d(8)ng (n=5-7), 4d(7)5s(2) and 4d(7)5p(2)] and 4p(5)4d(10), 4p(6)[4d(8)np (n=5-7), 4d(8)nf (n=4-6), 4d(8)nh (n = 6-7), 4d(7)5s5p and 4d(7)5s4f] were incorporated in the even and odd parity systems, respectively. The previous analyses were checked thoroughly; five levels of 4d(8)5p were revised and two configurations, viz., 4d(8)5d and 4d(8)6s have been investigated for the first time. A total of 124 energy levels were established belonging to the configurations 4p(6)[4d(9)+4d(8)(5s + 6s + 5p+ 5d)], among which 64 levels of 4p(6)4d(8)(5d + 6s) were newly established. Least squares fitting parametric calculations were carried out to interpret the observed energy level structure. The observed energy levels were optimized to fit the measured wavelengths. (C) 2018 Elsevier Ltd. All rights reserved.