Wavelengths and energy levels of neutral Kr-84 and level shifts in all Kr even isotopes

Abstract

Interferometrically-measured wavelengths of 109 lines of neutral Kr-84 are compared with those of Kr-86. Sixty energy levels of neutral Kr-84 derived from those wavelengths and 25 Kr-86-Kr-84 isotope shifts previously measured are given along with their shifts from the energy levels of Kr-86. Twenty levels of each of Kr-82, Kr-80, and Kr-78 are also evaluated using isotope-shift information in the literature. The differences between the experimentally observed shifts and the normal mass shift leave large negative residuals which are accounted for by ionization energy differences and by the specific mass shift. It appears that the volume effect causes only a very small, if any, energy level shift.