Analysis of Soft X-Ray Photoelectric Yield and Absorption Spectra by Potential Scanning Technique–LiF and NaF near the F K-Absorption Edge–

1981 ◽  
Vol 20 (10) ◽  
pp. 1939-1945
Author(s):  
Takeshi Muranaka ◽  
Setsuo Kiyono ◽  
Takeshi Watanabe
Keyword(s):  
Absorption Spectra ◽  
Absorption Edge ◽  
X Ray ◽  
Scanning Technique

scholarly journals Finite lifetime broadening of calculated X-ray absorption spectra: possible artefacts close to the edge

2018 ◽  
Vol 25 (2) ◽  
pp. 523-528 ◽  
Author(s):  
Ondřej Šipr ◽  
Jiří Vackář ◽  
Ján Minár
Keyword(s):  
Absorption Spectra ◽  
Real Axis ◽  
Absorption Edge ◽  
Spectral Features ◽  
Core Hole ◽  
Energy Component ◽  
X Ray ◽  
The Core ◽  
X Ray Absorption ◽  
Small Imaginary Part

X-ray absorption spectra calculated within an effective one-electron approach have to be broadened to account for the finite lifetime of the core hole. For methods based on Green's function this can be achieved either by adding a small imaginary part to the energy or by convoluting the spectra on the real axis with a Lorentzian. By analyzing the FeK- andL2,3-edge spectra it is demonstrated that these procedures lead to identical results only for energies higher than a few core-level widths above the absorption edge. For energies close to the edge, spurious spectral features may appear if too much weight is put on broadeningviathe imaginary energy component. Special care should be taken for dichroic spectra at edges which comprise several exchange-split core levels, such as theL3-edge of 3dtransition metals.

X-Ray Study of the Band Structure in Stannic Oxide

1979 ◽  
Vol 23 ◽  
pp. 203-207
Author(s):  
A. A. Bahgat ◽  
K. Das Gupta
Keyword(s):  
Absorption Spectra ◽  
Absorption Edge ◽  
Low Energy ◽  
Stannic Oxide ◽  
Crystal Spectrometer ◽  
White Line ◽  
X Ray ◽  
Bent Crystal ◽  
The Continuum ◽  
Energy Side

In this article we present the experimental data on L3-absorption spectra of metallic tin. and tin in SnO2 . We have used (i) a bent crystal spectrometer and (ii) a high resolution flat crystal spectrometer with a microfocus target as the source for the continuum radiation. We have observed a “white line” on the low energy side of the primary L3-absorption edge of Sn in SnO2. Similar “white lines” in absorption spectra were reported earlier by M. Siegbahn in rare earth elements with f-vancies, who designated such lines appearing immedlately on the low energy side of the primary absorption edge as “white lines” in absorption spectra. It is interesting to note that metallic tin does not reveal the “white line”, while Sn in SnO2 clearly revealed a sharp white line on the low energy side of the primary absorption edge.

scholarly journals Dispersive X-Ray Synchrotron Studies of Pt-C Multilayers

1988 ◽  
Vol 143 ◽  
Author(s):  
B. Rodricks ◽  
F. Lamelas ◽  
D. Medjahed ◽  
W. Dos Passos ◽  
R. Smither ◽  
...  
Keyword(s):  
High Resolution ◽  
Absorption Spectra ◽  
Absorption Edge ◽  
Optical Constants ◽  
Scattering Data ◽  
X Ray ◽  
Simultaneous Acquisition ◽  
Ccd Detector ◽  
Synchrotron Studies ◽  
X Ray Absorption

AbstractWe demonstrate the simultaneous acquisition of high-resolution x-ray absorption spectra and scattering data, using a combination of energy-dispersive optics and a twodimensional CCD detector. Results are presented on the optical constants of Pt and on the reflectivity of a platinum-carbon multilayer at the LIII absorption edge of Pt.

X-Ray absorption edge elemental imaging of B. thuringienis

1989 ◽  
Vol 47 ◽  
pp. 212-213
Author(s):  
R. L. Stears
Keyword(s):  
Absorption Edge ◽  
Elemental Distribution ◽  
X Rays ◽  
Differential Absorption ◽  
Synchrotron Source ◽  
High Brightness ◽  
X Ray ◽  
Elemental Imaging ◽  
Cellular Integrity ◽  
X Ray Absorption

Because of the nature of the bacterial endospore, little work has been done on analyzing their elemental distribution and composition in the intact, living, hydrated state. The majority of the qualitative analysis entailed intensive disruption and processing of the endospores, which effects their cellular integrity and composition.Absorption edge imaging permits elemental analysis of hydrated, unstained specimens at high resolution. By taking advantage of differential absorption of x-ray photons in regions of varying elemental composition, and using a high brightness, tuneable synchrotron source to obtain monochromatic x-rays, contact x-ray micrographs can be made of unfixed, intact endospores that reveal sites of elemental localization. This study presents new data demonstrating the application of x-ray absorption edge imaging to produce elemental information about nitrogen (N) and calcium (Ca) localization using Bacillus thuringiensis as the test specimen.

Electronic Structure and X-ray Absorption Spectra of Rutile TiO2 Using First-Principles Calculations

2014 ◽  
Vol 52 (12) ◽  
pp. 1025-1029
Author(s):  
Min-Wook Oh ◽  
Tae-Gu Kang ◽  
Byungki Ryu ◽  
Ji Eun Lee ◽  
Sung-Jae Joo ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Absorption Spectra ◽  
First Principles ◽  
First Principles Calculations ◽  
Rutile Tio2 ◽  
X Ray ◽  
X Ray Absorption

scholarly journals Modeling of the Resonant X-ray Response of a Chiral Cubic Phase

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 214
Author(s):  
Timon Grabovac ◽  
Ewa Gorecka ◽  
Damian Pociecha ◽  
Nataša Vaupotič
Keyword(s):  
Absorption Edge ◽  
Unit Cell ◽  
Resonant Peak ◽  
Cubic Phase ◽  
Tensor Form ◽  
Resonant Enhancement ◽  
X Ray ◽  
X Ray Scattering ◽  
Thermotropic Liquid Crystals ◽  
Carbon Absorption

The structure of a continuous-grid chiral cubic phase made of achiral constituent molecules is a hot topic in the field of thermotropic liquid crystals. Several structural models have been proposed so far. Resonant X-ray scattering (RXS), which gives information on the molecular orientation in the unit cell, could be applied to select the most appropriate model. We modeled the RXS response for the recently proposed chiral cubic phase structure with an all-hexagon chiral continuous grid. A tensor form factor of a unit cell is constructed, which enables calculation of intensities of peaks for all Miller indices. We find that all the symmetry allowed peaks are resonantly enhanced, and their intensity is much stronger than the intensity of the symmetry forbidden (resonant) peaks. In particular, we predict that a strong resonant enhancement of the symmetry allowed peaks (011) and (002), not observed in a nonresonant scattering, could be observed by RXS at the carbon absorption edge. By RXS at the sulfur absorption edge, one might observe a resonant peak (113) and resonantly enhanced peak (233), and resonant enhancement of all the peaks that are observed in a nonresonant scattering, which probably hide the rest of the predicted resonant peaks.

scholarly journals Theoretical description of optical and x-ray absorption spectra of MgO including many-body effects

2021 ◽  
Vol 103 (19) ◽  
Author(s):  
Vijaya Begum ◽  
Markus E. Gruner ◽  
Christian Vorwerk ◽  
Claudia Draxl ◽  
Rossitza Pentcheva
Keyword(s):  
Absorption Spectra ◽  
Theoretical Description ◽  
Many Body ◽  
X Ray ◽  
Many Body Effects ◽  
X Ray Absorption
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