Long-wavelength transitions and improved energy levels of triply ionized zirconium (Zr IV)

This is the authors' abstract. We don't add key points for this paper.

Fourteen new spectral lines of Zr iv lying between 3200 and 4600 Å were observed with a sliding spark discharge and a 10.7-m normal-incidence spectrograph. The lines were classified as transitions between highly excited energy levels of this ion. The measured wavelengths provide improved values for the known energy levels as well as a value for the previously unknown 6h 2H term. Wavelengths with standard uncertainties varying from ±0.0005 to ±0.0018 Å were determined from the optimized level values for a group of lines between 445 and 1291 Å. An improved ionization energy was determined as 277 602.8±0.5 cm-1(34.41837±0.00006 eV).