The Spectrum of Four Times Ionized Scandium, ScV

Abstract

The spectrum of four times ionized scandium emitted from a sliding spark discharge has been observed using a 3 m normal incidence spectrograph and a 5 m grazing incidence spectrograph. About 450 lines in the wavelength region 160 A to 2200 A have been identified as combinations between 46 odd levels belonging to the 3s23ps, 3s23p4 4 p and 3s3p5 3d configurations and 1 2 even levels of the 3s3p6, 3s23p4 3d, 4d, 4s and 5s configurations. Of the previous identifications we have confirmed 18 levels. The level structure of the observed configurations has been theoretically interpreted by including configuration interaction effects. The inclusion of 3s23p3 3d2 in the calculations of the odd parity configurations is found to be important. Almost all levels of 3s3p5 3d show a considerable mixing with levels of 3s23p33dZ, in some cases by as much as 50%. The energy parameters determined from least-squares fits to the observed level values are compared with Hartree-Fock calculations. The ionization energy is estimated to be 739 500 -f lOOOcm-'. (91.65 i 0.12eV).

R-matrix calculation of the photoabsorption of K II, Ca III and Sc IV

“…The agreement between theory and experiment is satisfactory since the differences are relatively small. For Sc V, we compare our results with the data of Smitt and Ekberg (1985) in table 3. Again agreement is satisfactory.…”

Extensive spectroscopic data for multiply ionized scandium: Sc III to Sc XXI

“…The NIST database gives 118 Sc v energy levels and 454 electric dipolar transitions, derived from the analysis of Smitt & Ekberg (1985). Theoretical oscillator strengths for K iii, Ca iv, and Sc v iosoelectronic spectra were published by Wilson et al (2000).…”

“…Smitt & Ekberg (1985) highlighted their mixed composition, with additional perturbation by the numerous unobserved levels of the 3s 2 3p 3 3d 2 configuration. The NIST level 3s3p 5 ( 3 P)3d 4 D 5/2 is labelled 4p by FAC, the mixing being calculated as 48%−34% by Smitt & Ekberg (1985).…”

“…Smitt & Ekberg (1985) highlighted their mixed composition, with additional perturbation by the numerous unobserved levels of the 3s 2 3p 3 3d 2 configuration. The NIST level 3s3p 5 ( 3 P)3d 4 D 5/2 is labelled 4p by FAC, the mixing being calculated as 48%−34% by Smitt & Ekberg (1985). On the even side, the 72 levels from the configurations 3s3p 6 , 3s 2 3p 4 3d, 3s 2 3p 4 4s, 3s 2 3p 4 4d, and 3s 2 3p 4 5s are observed and matched to the FAC levels, except for the 3s 2 3p 4 ( 3 P)5s 4 P 5/2 level, which is unobserved.…”

Oscillator Strengths for K III, Ca IV and Sc V

“…However, the present work is of a much larger scale than either previous calculation and we are con¢dent in the accuracy of our results. Table IX we compare the LS energy levels obtained in the present calculation with those of Smitt and Ekberg [6], obtained using the Cowan code [7], where the ¢ne structure levels of Smitt and Ekberg for each state have been averaged using their statistical weights. The results show very good accord between theory and experiment.…”