A Critical Compilation of Energy Levels in the Configurations 2sm2pk(m=2, 1, 0) of F I-, O I- and Be I-like Spectra

Existing observations of transitions 2 s 2 2 p k -2 s 2 p k +1 and 2 s 2 p k +1 -2 p k +2 in F I-, O I- and Be I-like spectra are collected and examined as to their isoelectronic consistency by plotting against Z appropriate functions of selected intervals. The functions are then expressed by polynomials of the fourth to the sixth degree, derived by a weighted least-squares fitting over a range of about twenty Z -values, up to Z = 33, 32 and 28 in the F I, O I and Be I sequences, respectively. In the case of the Be I sequence, a previous investigation is now extended with the aid of new observations by Lawson and Peacock for Z = 24-28. For all three sequences the results of the examination are presented in tables of recommended level values and recalculated wavelengths.