Structure and Line Strengths in ExtremejKCoupling: An Experimental and Theoretical Study in Ni II

The spectrum emitted from a nickel hollow cathode has been recorded with a Fourier transform spectrometer. Two dense groups of lines just above 18 000 Å have been identified as the transitions 3 d 8 ( 3 F )5 f -3 d 8 ( 3 F )6 g and 3 d 8 ( 3 F )5 g -3 d 8 ( 3 F )6 h in Ni II. The level structure of the configurations involved in these transitions has been studied by fitting the Slater parameters of the energy matrices to the observations. The fitted parameters have been used for calculating the relative line strengths in the transition arrays. Comparisons with the observed intensities show very good agreement.