Predictions of atomic energy levels by extrapolation along isoelectronic sequences: helium through sodium.

Abstract

Approximately 900 unknown atomic energy levels were predicted by extrapolation along the helium through sodium isoelectronic sequences. The extrapolations, based on well known regularities in atomic spectra, extend beyond the range of known values providing predictions in highly ionized atoms. The predicted energy levels are presented, along with the known values, in tabular form. In addition, as an aid to spectroscopists, 116 transitions are listed with known and predicted wavelengths. Since the majority of the energy level predictions are in highly ionized atoms, most of the predicted wavelengths fall in the vacuum ultraviolet region of the spectrum.