Atomic isotope shifts in the spectra of dysprosium, erbium, and ytterbium have been measured using enriched samples and a Fabry-Perot interferometer. Results include new data on 5 lines in DyI, on 71 lines in ErI, and for 89 lines in YbI. Correlation of electron configurations indicates that for these elements ƒn6s7s-ƒn6s6p transitions show an average isotope shift of +28 mK, ƒn-15d6s6p-ƒn-15d6s2 exhibit shifts of -86 mK, ƒn5d6s–ƒn-15d6s2 lines have shifts of - 105mK, ƒn-15d26s-ƒn6s2 show shifts of -20 mk, while ƒ26s6d-ƒn6s6p and ƒn-16p6s2-ƒn-15d6s2 transitions exhibit no detectable shifts. Using these isotope shift trends, 17 levels of YbI have been identified as belonging to 4ƒ135d6s6p configurations.
© 1976 Optical Society of America
Glenn E. Millerand and John S. Ross, "Isotope shifts in the arc spectra of dysprosium, erbium, and ytterbium," J. Opt. Soc. Am. 66, 585-589 (1976)