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 (<sup>7</sup><i>P</i>, <sup>9</sup><i>F</i>, <sup>9</sup><i>D</i>, <sup>7</sup><i>D</i>) of the configuration 4ƒ<sup>7</sup>(<sup>8</sup><i>S</i><sub>3½</sub>)5<i>d</i>6<i>s</i>6<i>p</i>. Russell’s prediction that the next even configuration, 4ƒ<sup>7</sup>(<sup>8</sup>S<sub>3½</sub>)5<i>d</i><sup>2</sup>6<i>p</i>, begins at ~25000 cm<sup>-1</sup> is confirmed. The observed <i>g</i>-values in general lie within ±5% of the <i>L</i>-<i>S</i> 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)