scholarly journals Electron Energy Loss Near Edge Structure (ELNES) on the Carbon K-Edge in Transition Metal Carbides with the Rock Salt Structure

1995 ◽  
Vol 6 (1) ◽  
pp. 89-98 ◽  
Author(s):  
Alan J. Craven ◽  
Laurence A. J. Garvie
Keyword(s):  
Transition Metal ◽  
Energy Loss ◽  
Electron Energy ◽  
Rock Salt ◽  
Metal Carbides ◽  
Rock Salt Structure ◽  
Edge Structure ◽  
Transition Metal Carbides ◽  
Salt Structure ◽  
Electron Energy Loss

Future Trends in Modeling Electron Energy Loss Near-Edge Structure (ELNES)

2000 ◽  
Vol 6 (S2) ◽  
pp. 180-181
Author(s):  
A. J. Scott ◽  
R. Brydson
Keyword(s):  
Energy Loss ◽  
Electron Energy ◽  
High Performance ◽  
Metal Carbides ◽  
Edge Structure ◽  
Augmented Plane Wave ◽  
Software Packages ◽  
Electron Energy Loss ◽  
Performance Computing ◽  
Structure Calculations

The increasing availability of fast, multiprocessor high performance computing facilities has revolutionized iterative electronic structure calculations of solids, particularly for those systems possessing little or no symmetry. This combined with the semi-commercial dissemination of well-supported software packages for the calculation of both occupied and unoccupied electronic states at high levels of approximation has opened up the possibilities for more routine modeling and understanding of electron energy loss near-edge structure (ELNES) data obtained in the TEM/STEM, and hence the elucidation of chemical bonding in solids at high spatial resolution.The two modeling approaches presented and compared here involve ab-initio band structure calculations based on the full linear augmented plane wave (FLAPW - WIEN97) approach, and full multiple scattering (MS) clusterbased methods. We have performed a systematic study of transition metal carbides and nitrides and compared the modeling results with high resolution EELS data.

Energy Loss by Channeled Electrons: A Quantitative Study on Transition Metal Oxides

2013 ◽  
Vol 19 (6) ◽  
pp. 1586-1594 ◽  
Author(s):  
Kazuyoshi Tatsumi ◽  
Shunsuke Muto ◽  
Ján Rusz
Keyword(s):  
Transition Metal ◽  
Energy Loss ◽  
Electron Energy ◽  
Transition Metal Oxides ◽  
Chemical Information ◽  
Specific Element ◽  
Edge Structure ◽  
Electron Microscopes ◽  
Site Selective ◽  
Electron Energy Loss

AbstractElectron energy-loss spectroscopy (EELS) attached to current transmission electron microscopes can probe not only element-selective chemical information, but also site-selective information that depends on the position that a specific element occupies in a crystal lattice. The latter information is exploited by utilizing the Bloch waves symmetry in the crystal, which changes with its orientation with respect to the incident electron wave (electron channeling). We demonstrate the orientation dependence of the cross-section of the electron energy-loss near-edge structure for particular crystalline sites of spinel ferrites, by quantitatively taking into account the dynamical diffraction effects with a large number of the diffracted beams. The theoretical results are consistent with a set of experiments in which the transition metal sites in spinel crystal structures are selectively excited. A new measurement scheme for site-selective EELS using a two-dimensional position-sensitive detector is proposed and validated by theoretical predictions and trial experiments.

Electron energy-loss near-edge structure in silicate minerals

1992 ◽  
Vol 50 (2) ◽  
pp. 1258-1259
Author(s):  
D W McComb ◽  
R S Payne ◽  
P L Hansen ◽  
R Brydson
Keyword(s):  
Solid State ◽  
Energy Loss ◽  
Electron Energy ◽  
State Energy ◽  
Local Environment ◽  
Edge Structure ◽  
Silicate Minerals ◽  
Two Samples ◽  
Electron Energy Loss ◽  
Careful Processing

Electron energy-loss near-edge structure (ELNES) is an effective probe of the local geometrical and electronic environment around particular atomic species in the solid state. Energy-loss spectra from several silicate minerals were mostly acquired using a VG HB501 STEM fitted with a parallel detector. Typically a collection angle of ≈8mrad was used, and an energy resolution of ≈0.5eV was achieved.Other authors have indicated that the ELNES of the Si L2,3-edge in α-quartz is dominated by the local environment of the silicon atom i.e. the SiO4 tetrahedron. On this basis, and from results on other minerals, the concept of a coordination fingerprint for certain atoms in minerals has been proposed. The concept is useful in some cases, illustrated here using results from a study of the Al2SiO5 polymorphs (Fig.l). The Al L2,3-edge of kyanite, which contains only 6-coordinate Al, is easily distinguished from andalusite (5- & 6-coordinate Al) and sillimanite (4- & 6-coordinate Al). At the Al K-edge even the latter two samples exhibit differences; with careful processing, the fingerprint for 4-, 5- and 6-coordinate aluminium may be obtained.

Combined ab-initio and N-K, Ti-L2,3, V-L2,3 electron energy-loss near edge structure studies for TiN and VN films

2007 ◽  
Vol 98 (11) ◽  
pp. 1060-1065 ◽  
Author(s):  
Boriana Rashkova ◽  
Petr Lazar ◽  
Josef Redinger ◽  
Raimund Podloucky ◽  
Gerald Kothleitner ◽  
...  
Keyword(s):  
Energy Loss ◽  
Ab Initio ◽  
Electron Energy ◽  
Edge Structure ◽  
Electron Energy Loss

The Use of ELNES for Microanalysis

1999 ◽  
Vol 5 (S2) ◽  
pp. 664-665
Author(s):  
A.J. Craven ◽  
M. MacKenzie
Keyword(s):  
Electron Microscopy ◽  
Energy Loss ◽  
Electron Energy ◽  
Analytical Electron Microscopy ◽  
Local Environment ◽  
Edge Structure ◽  
Similar Shape ◽  
Analytical Electron ◽  
Electron Energy Loss ◽  
Combining Information

The performance of many materials systems depends on our ability to control the distribution of atoms on a nanometre or sub-nanometre scale within those systems. This is as true for steels as it is for semiconductors. A key requirement for improving their performance is the ability to determine the distribution of the elements resulting from processing the material under a given set of conditions. Analytical electron microscopy (AEM) provides a range of powerful techniques with which to investigate this distribution. By combining information from different techniques, many of the ambiguities of interpretation of the data from an individual technique can be eliminated. The electron energy loss near edge structure (ELNES) present on an ionisation edge in the electron energy loss spectrum reflects the local structural and chemical environments in which the particular atomic species occurs. Thus it is a useful contribution to the information available. Since a similar local environment frequently results in a similar shape, ELNES is useful as a “fingerprint”.

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