199 Zeeman patterns are presented for Gd I, from which g-values are calculated for 118 levels. A discussion is given of the terms and electron configurations to which previously unassigned even levels may belong; new assignments are given for 15 even levels belonging to four terms (7P, 9F, 9D, 7D) of the configuration 4ƒ7(8S3½)5d6s6p. Russell’s prediction that the next even configuration, 4ƒ7(8S3½)5d26p, begins at ~25000 cm-1 is confirmed. The observed g-values in general lie within ±5% of the L-S coupling values, but marked deviations occur for some levels, indicating that energy-level mixing is present.
ERIC H. PINNINGTON, "Zeeman-Effect Analysis of the Spectrum of Neutral Gadolinium (Gd I)," J. Opt. Soc. Am. 57, 1252-1252 (1967)