Strong Lines of Aluminum ͑Al͒-Continued IntensityWavelength ͑Å͒ Spectrum Ref

A new internally contracted multi-reference configuration interaction method

Following a critical review of spectroscopic data for neutral strontium ͑Z=38͒, the energy levels, with designations and uncertainties, have been tabulated. Wavelengths with classifications, intensities, and transition probabilities have also been reviewed. In addition, the 5s 2 S 1/2 , 4d 2 D 3/2 , and 4d 2 D 5/2 ionization energies have been listed. A summary of the current state of measurements of the Sr I 5s 2 1 S 0-5s5p 3 P 0 ‫ؠ‬ , F =9/ 2 atomic clock transition, and other isotopic observations has also been included.

Energy levels, with designations and uncertainties, have been compiled for the spectra of the neutral atom and all positive ions of rubidium (Zϭ37). Wavelengths with classifications, intensities, and transition probabilities are also tabulated. In addition, ground states and ionization energies are listed. For most ionization stages experimental data are available; however for ionization stages where only theoretical calculations or fitted values exist, these are reported. There are a few ionization stages for which only a calculated ionization potential is available.

The spectrum of a platinum hollow-cathode lamp containing neon carrier gas was recorded photographically and photoelectrically with a 10.7 m normal-incidence vacuum spectrograph. Wavelengths and intensities were determined for about 5600 lines in the region 1130–4330 Å. An atlas of the spectrum is given, with the spectral lines marked and their intensities, wavelengths, and classifications listed. Lines of impurity species are also identified. The uncertainty of the photographically measured wavelengths is estimated to be ± 0.0020 Å. The uncertainty of lines measured in the photoelectric scans is 0.01 Å for wavelengths shorter than 2030 Å and 0.02 Å for longer wavelengths. Ritz-type wavelengths are given for many of the classified lines of Pt II with uncertainties varying from ±0.0004 to ± 0.0025 Å. The uncertainty of the relative intensities is estimated to be about 20%.