Absorption-line series in Lu I

Abstract

The absorption spectrum of lutetium vapor in the ultraviolet region has been photographed, using the Argonne thirty-foot spectrograph and an inductively heated furnace. Two hundred lines have been measured with an accuracy of ± 0.004 Å, and approximately 91 % of these have been classified as members of six previously unobserved Rydberg series. Four of these involve transitions from the two lowest lying levels, 5 d 6 s2(2D3/2, 5/2), and two from the first excited multiplet, 6 s2 6 p(2P01/2, 3/2), which is sufficiently populated at the temperature used in the experiment. A value for the first ionization limit of Lu I has been derived from the extrapolation of the serie 5 d 6 s2(2D5/2)-nf 6 s2(2F07/2), which was measured to n = 36 and wich is pratically unperturbed. The value found was 43 762.39 ± 0.10 cm-1

Excitation of doublet D-levels of a lutetium atom by electron impact

“…The values of the wavelengths in Tables 1 and 2 are given according to the data from [8,10]. It should be noted that, in [8], many lines in the spectral range of 409-517 nm were attributed to the spectrum of lute tium monoxide LuO; however, under our experimen tal conditions, lines of this compound cannot occur.…”

“…Somewhat later, in [11], the emission IR spectrum of the lutetium atom was investigated and a theoretical analysis was performed that made it possible to classify more than 130 spectral lines of Lu I with wavelengths λ > 1 μm. In this case, eight even and five odd previously unknown levels of Lu I were proposed and some lines from [10] were reinterpreted, as a result of which all the principal quantum numbers for the 2 P° and 2 F° series that were proposed in [10] were decreased by unity. In addition, in [11], the energies of some low lying even levels included in the compilation of [2] were refined and the interpretation of the levels was changed.…”

“…In [10] the spectrum of Lu I in the UV range was studied by the absorption method, which made it pos sible to detect six previously unobserved Rydberg series. It was found that only the series 5d6s 2 2 D 5/2 -nf6s 2 is free from strong perturbations.…”

Electric Dipole Transitions for Lu I (Z = 71)

“…A double-resonance investigation of excited states of Lu I was carried out by Göbel [9]. Camus and Tomkins [10] photographed the absorption spectrum of lutetium vapor in the ultraviolet region using the Argonne thirty-foot spectrograph. A theoretical study of the odd configurations 5d6s6 p, 6s 2 6 p, 5 f 6s 2 and 5d 2 6 p of Lu I was presented by Camus and Masmoudi [11].…”

Time-resolved laser-induced fluorescence measurements of Rydberg states in Lu I and comparison with theory

“…In fact the NIST compilation is firstly based on levels deduced by Scribner (1930, 1937), who made arc and spark observations in the 250-1077 nm region. Extensions of the analysis are due to Klinkenberg (1954) and Camus and Tomkins (1972), who made observations in the 228-370 nm region. Additional contributions are due to Pinnington (1963).…”