Correlation between interatomic distances and the x-ray-absorption near-edge structure of single-crystal sapphire

Abstract

The high-resolution Al L-edge x-ray-absorption near-edge structure from single-crystal sapphire has been recorded by measuring the total-electron yield and x-ray-fluorescence yield with synchrotron radiation. The edge structures up to 11 eV from the absorption edge are assigned in terms of the transitions of Al 2p electrons to empty levels using molecular-orbital calculations. The post-edge features between 11 and 60 eV above the Al L» absorption edge were found to correlate very well with the interatomic distances from the absorbing atom to its neighboring atoms as predicted by the multiple-scattering model.

Spatially resolved nanoscale chemical and mechanical characterization of ZDDP antiwear films on aluminum?silicon alloys under cylinder/bore wear conditions

“…Peak a (doublet) in the FY spectrum is due to the transition of electrons from the 2p to 3s-like a orbitals in metallic aluminum and peak b, in the TEY spectrum is the corresponding transition for aluminum oxide. Broad peak c, is due to the transition of electrons to 3p-like t orbitals of aluminum oxide species [63]. It can be observed that the TEY spectrum of the antiwear film shows the presence of both metallic aluminum and aluminum oxide species; whereas the FY spectrum show mostly metallic Al and a trace of aluminum oxide, in contrast to Si (figure 3(a), bottom).…”

Coordination nature of aluminum (oxy)hydroxides formed under the influence of tannic acid studied by X-ray absorption spectroscopy

“…2. The Al L-edge spectra of different types of Al oxides and AlPO 4 have been reported using ELNES (Jiang et al, 2002;Bouchet and Colliex, 2003) and XANES (Chen et al, 1993). For minerals that are well crystalline, the first transition in the Al L-edge is usually split into two peaks with a separation of 0.45 eV [e.g., a-Al 2 O 3 (Chen et al, 1993) and AlPO 4 (personal communication with G.S.…”

XANES investigation of the Co oxidation state in solution and in cancer cells treated with Co(III) complexes

“…The post-edge minimum feature is a consequence of multiple-scattering phenomena which have been shown to be dependent on interatomic distances and angles [30][31][32].…”