CHARACTERIZATION OF 3D TRANSITION-METAL DIBORIDES BY X-RAY-ABSORPTION SPECTRA AT THE METAL K EDGE

The 3d transition-metal diborides TiB 2, VB 2 and CrB 2 have been characterized by X-ray absorption near-edge-structure (XANES) spectroscopy at the metal K edges. XANES spectra at the Ti , V and Cr K -edges of TiB 2, VB 2 and CrB 2, respectively, show similar spectral features up to an energy of about 70 eV above threshold. These features can be correlated to their specific atomic arrangement and electronic structure via multiple-scattering calculations as a function of the cluster size. Actually the second pre-edge feature is assigned to a transition from the metal 1s core state to the central metal 4p state hybridized with 3d band state of the higher-shell metal atoms. The first weak feature on the rising part of the edge is due to higher-shells multiple scattering contributions, suggesting that the transition features at the metal K -edge XANES of 3d transition-metal diborides are strongly affected by medium or long-range order contributions.

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Lattice dynamics study of AlB2-type 4d transition-metal diborides by extended X-ray-absorption fine structure

Radiation Physics and Chemistry ◽

10.1016/j.radphyschem.2005.07.061 ◽

2006 ◽

Vol 75 (11) ◽

pp. 2080-2084 ◽

Cited By ~ 3

Author(s):

Wangsheng Chu ◽

Ziyu Wu ◽

Wenhan Liu ◽

N.L. Saini ◽

A. Bianconi ◽

...

Keyword(s):

Fine Structure ◽

Transition Metal ◽

Lattice Dynamics ◽

X Ray ◽

Absorption Fine ◽

Metal Diborides ◽

X Ray Absorption ◽

Transition Metal Diborides

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Database of ab initio L-edge X-ray absorption near edge structure

Scientific Data ◽

10.1038/s41597-021-00936-5 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Yiming Chen ◽

Chi Chen ◽

Chen Zheng ◽

Shyam Dwaraknath ◽

Matthew K. Horton ◽

...

Keyword(s):

High Throughput ◽

Scattering Theory ◽

Research Community ◽

Metal Compounds ◽

Edge Structure ◽

X Ray ◽

Initial Release ◽

Computational Workflow ◽

X Ray Absorption

AbstractThe L-edge X-ray Absorption Near Edge Structure (XANES) is widely used in the characterization of transition metal compounds. Here, we report the development of a database of computed L-edge XANES using the multiple scattering theory-based FEFF9 code. The initial release of the database contains more than 140,000 L-edge spectra for more than 22,000 structures generated using a high-throughput computational workflow. The data is disseminated through the Materials Project and addresses a critical need for L-edge XANES spectra among the research community.

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Characterization of As-doped, p-type ZnO by x-ray absorption near-edge structure spectroscopy: Theory

Applied Physics Letters ◽

10.1063/1.2398895 ◽

2006 ◽

Vol 89 (22) ◽

pp. 222113 ◽

Cited By ~ 33

Author(s):

Sukit Limpijumnong ◽

M. F. Smith ◽

S. B. Zhang

Keyword(s):

Edge Structure ◽

X Ray ◽

P Type ◽

X Ray Absorption

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Extended X-ray absorption fine structure and multiple-scattering simulation of nickel dithiolene complexes Ni[S2C2(CF3)2]2n(n= −2, −1, 0) and an olefin adduct Ni[S2C2(CF3)2]2(1-hexene)

Journal of Synchrotron Radiation ◽

10.1107/s1600577514025041 ◽

2015 ◽

Vol 22 (1) ◽

pp. 124-129 ◽

Cited By ~ 4

Author(s):

Weiwei Gu ◽

Hongxin Wang ◽

Kun Wang

Keyword(s):

Fine Structure ◽

Multiple Scattering ◽

Edge Structure ◽

X Ray ◽

Absorption Fine ◽

Square Planar ◽

Square Planar Complexes ◽

Uv Visible ◽

Edge Features ◽

X Ray Absorption

A series of Ni dithiolene complexes Ni[S2C2(CF3)]2n(n= −2, −1, 0) (1,2,3) and a 1-hexene adduct Ni[S2C2(CF3)2]2(C6H12) (4) have been examined by NiK-edge X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine-structure (EXAFS) spectroscopies. Ni XANES for1–3reveals clear pre-edge features and approximately +0.7 eV shift in the NiK-edge position for `one-electron' oxidation. EXAFS simulation shows that the Ni—S bond distances for1,2and3(2.11–2.16 Å) are within the typical values for square planar complexes and decrease by ∼0.022 Å for each `one-electron' oxidation. The changes in NiK-edge energy positions and Ni—S distances are consistent with the `non-innocent' character of the dithiolene ligand. The Ni—C interactions at ∼3.0 Å are analyzed and the multiple-scattering parameters are also determined, leading to a better simulation for the overall EXAFS spectra. The 1-hexene adduct4presents no pre-edge feature, and its NiK-edge position shifts by −0.8 eV in comparison with its starting dithiolene complex3. Consistently, EXAFS also showed that the Ni—S distances in4elongate by ∼0.046 Å in comparison with3. The evidence confirms that the neutral complex is `reduced' upon addition of olefin, presumably by olefin donating the π-electron density to the LUMO of3as suggested by UV/visible spectroscopy in the literature.

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Characterization of selenium speciation in selenium-enriched button mushrooms (Agaricus bisporus) and selenized yeasts (dietary supplement) using X-ray absorption near-edge structure (XANES) spectroscopy

Journal of Trace Elements in Medicine and Biology ◽

10.1016/j.jtemb.2018.10.018 ◽

2019 ◽

Vol 51 ◽

pp. 164-168 ◽

Cited By ~ 4

Author(s):

Alexander Prange ◽

Miriam Sari ◽

Susanne von Ameln ◽

Csaba Hajdu ◽

Reinhard Hambitzer ◽

...

Keyword(s):

Dietary Supplement ◽

Agaricus Bisporus ◽

Xanes Spectroscopy ◽

Selenium Speciation ◽

Edge Structure ◽

X Ray ◽

Button Mushrooms ◽

X Ray Absorption

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Oxygen X-ray absorption near-edge structure characterization of the Ba-doped yttria oxidative coupling catalyst

Journal of Catalysis ◽

10.1016/0021-9517(92)90102-n ◽

1992 ◽

Vol 136 (1) ◽

pp. 16-23 ◽

Cited By ~ 10

Author(s):

M KAMINSKY

Keyword(s):

Oxidative Coupling ◽

Structure Characterization ◽

Edge Structure ◽

X Ray ◽

X Ray Absorption

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X -Ray Absorption Near Edge Structure (XANES) Calculations for the Amorphous Fe80B20- and Ni80B20-Alloys

Zeitschrift für Naturforschung A ◽

10.1515/zna-1989-0304 ◽

1989 ◽

Vol 44 (3) ◽

pp. 189-194

Author(s):

P. Kizler ◽

P. Lamparter ◽

S. Steeb

Keyword(s):

Multiple Scattering ◽

Scattering Theory ◽

Edge Structure ◽

Multiple Scattering Theory ◽

X Ray ◽

Bond Angles ◽

Complex Features ◽

X Ray Absorption ◽

Good Agreement

Xanes spectra of the amorphous Fe80B20- and Ni80B20-alloys have been investigated using the electron multiple scattering theory of Durham et al. The calculations were based on several models for the structure of amorphous Fe80B20 and Ni80B20. Very good agreement between theoretical and experimental XANES curves was met. Opposite to former expectations for obtaining information on bond angles by XANES, this study shows that XANES points to more complex features of the structure than can be expressed in terms of bond angles.

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