B. Sonntag

Optical absorption measurements of the transition metals Ti, V, Cr, Mn, Fe, Co, Ni in the region of 3p electron transitions

Abstract Using the continuous spectrum of synchrotron radiation, the absolute absorption coefficient of seven transition metals has been determined in the spectral range 40–300eV. The strong oscillations reported by previous investigators appear to have been spurious.

OPTICAL ABSORPTION OF CERIUM, CERIUM OXIDE, PRASEODYMIUM, PRASEODYMIUM OXIDE, NEODYMIUM, NEODYMIUM OXIDE, AND SAMARIUM IN THE EXTREME ULTRAVIOLET.

Abstract The optical absorption of the rare earths Ce, Pr, Nd and Sm has been measured in the energy region 100 eV – 180 eV. The absorption spectra of the oxides of Ce, Pr and Nd have been determined in the same energy region. Synchrotron radiation of the 7.5 GeV electron synchrotron DESY was used as a light source. Transitions from the 4 d level of the rare earths contribute the main part of the absorption in this energy region. At the onset of these transitions we found a number of sharp absorption maxima. This fine structure is followed by a broad absorption maximum, about 15 eV above the onset of 4 d transitions, which is due to d → f continuum transitions. The absorption spectra of Ce and Ce-oxide show a marked difference whereas the absorption spectra of Pr and Nd are very similar to those of their oxides.

Photoabsorption of Atomic Sodium in the VUV

The absorption spectrum of atomic sodium in the photon energy region from 30 to 150 eV has been investigated. A great number of sharp absorption lines which can be attributed to the excitation of a 2p- or a 2s-electron has been detected. Simultaneous excitation of one 2p- and one 3s-electron gives rise to considerably strong broad and asymmetric absorption structures above the highest series limit (1P1) for the excitations of a single 2p-electron. Some of the assignments have been confirmed by Hartree-Fock calculations. The relative spectral dependence of the absorption cross-section in this energy range has been determined for the first time. The spectrum of free Na atoms has been compared with theLII, III spectrum of solid sodium.

3p-excitation of atomic Mn; experimental evidence for the super Coster-Kronig decay

Abstract The experimental 3p-spectrum of atomic Mn is shown to be in good agreement with theoretical results based on the interference between the 3p63d54s2 → 3p53d64s2 and the 3 p 6 3 d 5 4 s 2 → 3 p 6 3 d 4 4 s 2 € f excitations mediated via the 3 p 5 3 d 6 4 s 2 → 3 p 6 3 d 4 4 s 2 € f super Coster-Kronig decay.

OPTICAL ABSORPTION MEASUREMENTS OF TANTALUM, TUNGSTEN, RHENIUM, AND PLATINUM IN THE EXTREME ULTRAVIOLET.

Abstract The absolute absorption coefficient of Ta, W, Re and Pt has been determined in the photon energy range 30–600eV by use of synchrotron radiation at the 7.5-GeV electron synchrotron DESY. The most prominent structure is a broad double peak, which is caused by transitions from the 5p shell into the empty d states of these transition metals.

Atomic character of the 4d-absorption of Ce metal: An experimental proof

Abstract The photoabsorption of atomic Ce has been determined in the energy range from 100 eV to 150 eV. Except for very small deviations, the 4d-spectra of atomic and metallic Ce are identical. The resonances near the 4d-threshold are ascribed to 4d 10 4f → 4d 9 4f 2 transitions.

Absorption measurements of copper, silver, tin, gold and bismuth in the far ultraviolet

Abstract The absorption coefficient of Cu, Ag, Sn, Au and Bi films of thickness from 50–6500 A have been studied in the spectral range from 50–350 A using the synchrotron radiation of the 6 GeV electron synchrotron DESY.

The influence of intershell interaction on the 3d and 5d branching ratio of Cu and Au

Abstract The intensity ratio of the photoelectrons emitted from the upper and the lower parts of the d bands of polycrystalline Cu and Au films has been determined in the photon energy range from 40 eV to 120 eV. Intershell interaction gives rise to a significant increase of this ratio at the Cu 3p and Au 5p threshold.