Experimental verification of the need for either jj or intermediate coupling in the 5f states of plutonium

2003 ◽  
Vol 802 ◽  
Author(s):  
K. T. Moore ◽  
M. A. Wall ◽  
A. J. Schwartz ◽  
B. W. Chung ◽  
J. G. Tobin ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Electron Microscope ◽  
Synchrotron Radiation ◽  
Single Phase ◽  
High Spatial Resolution ◽  
Intermediate Coupling ◽  
X Ray ◽  
Transmission Electron ◽  
Electron Energy Loss ◽  
X Ray Absorption

ABSTRACTHere, we demonstrate the power of electron energy-loss spectroscopy (EELS) in a transmission electron microscope (TEM) to investigate the electronic structure plutonium. Using EELS, TEM, and synchrotron-radiation-based X-ray absorption spectroscopy (XAS), we provide the first experimental evidence that Russell-Saunders (LS) coupling fails for the 5f states of Pu. These results support the assumption that only the use of jj or intermediate coupling is appropriate for the 5f states of Pu. EELS experiments were performed in a TEM and are coupled with image and diffraction data, therefore, the measurements are completely phase specific. It is shown that EELS in a TEM may be used to circumvent the difficulty of producing single-phase or single-crystal samples due to its high spatial resolution.

Correlative electron and X-ray microscopy: probing chemistry and bonding with high spatial resolution

Nanoscale ◽  
2015 ◽  
Vol 7 (5) ◽  
pp. 1534-1548 ◽  
Author(s):  
Angela E. Goode ◽  
Alexandra E. Porter ◽  
Mary P. Ryan ◽  
David W. McComb
Keyword(s):  
Electron Microscope ◽  
Energy Loss ◽  
Transmission Electron Microscope ◽  
High Spatial Resolution ◽  
Scanning Transmission Electron Microscope ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Electron Energy Loss ◽  
X Ray Absorption

Benefits and challenges of correlative spectroscopy: electron energy-loss spectroscopy in the scanning transmission electron microscope (STEM-EELS) and X-ray absorption spectroscopy in the scanning transmission X-ray microscope (STXM-XAS).

High Spatial Resolution Compositional Analysis at Interfaces

1980 ◽  
Vol 38 ◽  
pp. 356-359
Author(s):  
John B. Vander Sande ◽  
Thomas F. Kelly ◽  
Douglas Imeson
Keyword(s):  
Electron Microscope ◽  
High Spatial Resolution ◽  
Compositional Analysis ◽  
Scanning Transmission Electron Microscope ◽  
Thin Specimen ◽  
X Ray ◽  
Volume Of Interest ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Electron Energy Loss

In the scanning transmission electron microscope (STEM) a fine probe of electrons is scanned across the thin specimen, or the probe is stationarily placed on a volume of interest, and various products of the electron-specimen interaction are then collected and used for image formation or microanalysis. The microanalysis modes usually employed in STEM include, but are not restricted to, energy dispersive X-ray analysis, electron energy loss spectroscopy, and microdiffraction.

X-ray microanalysis of thin specimens in the transmission electron microscope at voltages up to 1000 Kv.

1978 ◽  
Vol 36 (1) ◽  
pp. 540-541
Author(s):  
G. Cliff ◽  
M.J. Nasir ◽  
G.W. Lorimer ◽  
N. Ridley
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Weight Fraction ◽  
Present Series ◽  
Constant Independent ◽  
X Ray ◽  
Transmission Electron ◽  
Series Of Experiments ◽  
Image Position ◽  
X Ray Absorption

In a specimen which is transmission thin to 100 kV electrons - a sample in which X-ray absorption is so insignificant that it can be neglected and where fluorescence effects can generally be ignored (1,2) - a ratio of characteristic X-ray intensities, I1/I2 can be converted into a weight fraction ratio, C1/C2, using the equationwhere k12 is, at a given voltage, a constant independent of composition or thickness, k12 values can be determined experimentally from thin standards (3) or calculated (4,6). Both experimental and calculated k12 values have been obtained for K(11<Z>19),kα(Z>19) and some Lα radiation (3,6) at 100 kV. The object of the present series of experiments was to experimentally determine k12 values at voltages between 200 and 1000 kV and to compare these with calculated values.The experiments were carried out on an AEI-EM7 HVEM fitted with an energy dispersive X-ray detector.

Effects of bond character on the electronic structure of brownmillerite-phase oxides, Ca2B′xFe2−xO5 (B′ = Al, Ga): an X-ray absorption and electron energy loss spectroscopic study

2009 ◽  
Vol 19 (48) ◽  
pp. 9213 ◽  
Author(s):  
Andrew P. Grosvenor ◽  
Farshid Ramezanipour ◽  
Shahab Derakhshan ◽  
Christian Maunders ◽  
Gianluigi A. Botton ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Energy Loss ◽  
Spectroscopic Study ◽  
Electron Energy ◽  
X Ray ◽  
Electron Energy Loss ◽  
X Ray Absorption ◽  
Bond Character

3C-, 4H- and 6H-SiC Bulks Studied by Silicon K-Edge X-Ray Absorption

2013 ◽  
Vol 740-742 ◽  
pp. 573-576 ◽  
Author(s):  
Wei Zeng ◽  
Zhe Chuan Feng ◽  
Rui Sheng Zheng ◽  
Ling Yun Jang ◽  
Chee Wei Liu
Keyword(s):  
Electronic Structure ◽  
Fine Structure ◽  
High Resolution ◽  
Synchrotron Radiation ◽  
Angular Dependence ◽  
Comparative Studies ◽  
X Ray ◽  
Absorption Fine ◽  
X Ray Absorption

High-resolution synchrotron radiation X-ray absorption of Si K-edge have been employed to investigate 6H-, 4H- and 3C-SiC. Detailed analyses of the extended x-ray absorption fine structure are taken by using the IFEFFIT program, and significant results on the atomic bonding are obtained from these comparative studies. The x-ray absorption near-edge structures of the Si K-edge are investigated, and the electronic structure of 3C-, 4H- and 6H-SiC are studied. In order to investigate the angular dependence, the x-ray absorption near-edge spectra were operated at 55o and 90o of the angle between the surface and the X-ray direction.

Hydrazine-controlled hydrothermal synthesis of Co9S8 from a homogeneous solution

1999 ◽  
Vol 14 (11) ◽  
pp. 4418-4420 ◽  
Author(s):  
J. H. Zhan ◽  
X. G. Yang ◽  
Y. Xie ◽  
D. W. Wang ◽  
Y. T. Qian ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Formation Process ◽  
Single Phase ◽  
Homogeneous Solution ◽  
Critical Factor ◽  
X Ray ◽  
Transmission Electron ◽  
Wet Chemical ◽  
Hydrazine Solution ◽  
Scherrer Method

Single-phase nanocrystalline Co9S8 was prepared by hydrothermal treatment of Co(Ac)2 and NH2CSNH2 in hydrazine solution at 170 °C. The products were characterized by x-ray powder diffraction (XRD) technique, transmission electron microscope (TEM), and wet chemical analysis. XRD indicated the product was the cubic Co9S8 phase. The relative crystallite size was 6.3 nm as determined by the Scherrer method. TEM images showed the particles were agglomerative. The electron diffraction pattern also revealed their nanocrystalline nature. In this hydrothermal formation process of Co9S8, hydrazine was a critical factor. The formation process is discussed.

The use of XANES and ELNES for the Characterisation of Stabilised Zirconia

2001 ◽  
Vol 699 ◽  
Author(s):  
David W. McComb ◽  
Sergei Ostanin ◽  
Dimitris Vlachos ◽  
Alan J. Craven ◽  
Michael W. Finnis ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Full Potential ◽  
Data Simulation ◽  
Edge Structure ◽  
Materials Analysis ◽  
X Ray ◽  
Lmto Method ◽  
Electron Energy Loss ◽  
X Ray Absorption ◽  
Atomic Coordinates

AbstractThe electron energy-loss near-edge structure (ELNES) and x-ray absorption near-edge structure (XANES) at the oxygen K-edge has been investigated in a range of yttria-stabilised zirconia (YSZ) materials. Analysis of near-edge structure reveals that both the crystallographic phase and the metal fraction of yttrium present can be determined directly from the oxygen K-edge data. Simulation of the ELNES/XANES was achieved using a pseudopotential based method to obtain the relaxed atomic coordinates combined with full-potential LMTO method to calculate the electronic structure.

Growth of Single-Phase 2H-SiC Layers by Vapor–Liquid–Solid Process

2010 ◽  
Vol 645-648 ◽  
pp. 45-48 ◽  
Author(s):  
Mamoru Imade ◽  
Shin Takeuchi ◽  
Masahiro Uemura ◽  
Masashi Yoshimura ◽  
Yasuo Kitaoka ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Carbon Source ◽  
Single Phase ◽  
X Ray Diffraction ◽  
Vapor Liquid Solid ◽  
X Ray ◽  
Transmission Electron ◽  
Vls Growth ◽  
Sic Film ◽  
Vapor Liquid

We attempted the vapor–liquid–solid (VLS) growth of SiC film in Si-Li solution using gaseous CH4 as a carbon source at 900 oC. A 100-m-thick liquid-phase epitaxy (LPE) layer was obtained on a 4H-SiC (0001) substrate under CH4 pressure of 0.9 MPa. X-ray diffraction (XRD) and a high-resolution transmission electron microscope (HR-TEM) measurement showed that the LPE layer was single-phase 2H-SiC. We concluded that VLS growth in Si-Li solution using gaseous CH4 as a carbon source is useful for growing single-phase 2H-SiC.

Sign in / Sign up

Export Citation Format

Share Document