Determination of Structure, Shape and Sizes of Clusters Using Radial Distribution Functions (RDF) Method

1992 ◽  
Vol 272 ◽  
Author(s):  
Pavel E. Kolosov ◽  
A. V. Bubnov

ABSTRACTThe theoretical reduced intensity of X-ray scattering i(S) may be calculated for a cluster of any structure using Debye's formula. The comparison of both experimental determination and model calculation of the RDF or i(S) allows, to make a conclusions about structure of materials in a wide region of interatomic distances. This is a very important for direct structure characterization of giant clusters, dispersed molybdenum sulfides etc.. The simple formula for the upper limit of interatomic distances when the data are collected at equidistant step on S – scatterinrg vector, may be used for the optimal experimental conditions selection.

1965 ◽  
Vol 20 (3) ◽  
pp. 325-335 ◽  
Author(s):  
C. N. J. Wagner ◽  
H. Ocken ◽  
M. L. Joshi

The x-ray scattering from liquid copper, silver, tin, and mercury was measured at temperatures of 1125°C, 1050°C, 335°C, and 28°C, respectively, from the open surface of horizontal samples using a focusing theta-theta diffractometer, quartz crystal monochromator positioned in the diffracted beam, scintillation detector, and pulse height discriminator. The effect on the measured intensities of the positioning of the sample with respect to the diffractometer axis and the meniscus of the liquid were considered. Calibration of the primary beam intensity by measurements on liquid mercury provided an alternate check of the standard normalization procedures for copper, silver, and tin. After calculation of the interference functions, atomic and radial distribution functions were evaluated from which interatomic distances and coordination numbers were obtained. The interatomic distances in the liquid were in good agreement with the GOLDSCHMIDT diameters of the respective elements.


1991 ◽  
Vol 46 (7) ◽  
pp. 605-608 ◽  
Author(s):  
E. Matsubara ◽  
Y. Waseda ◽  
A. P. Tsai ◽  
A. Inoue ◽  
T. Masumoto

A structural study of an as-quenched decagonal Al75Fe15Ni10 alloy has been carried out by anomalous x-ray scattering (AXS) as well as ordinary x-ray diffraction. The environmental radial distribution functions (RDFs) for Fe and Ni determined by the AXS measurements turned out to resemble each other and to be similar to the ordinary RDF obtained by ordinary x-ray diffraction. These results clearly show that the Ni and Fe atoms are homogeneously distributed and occupy the same sites in the decagonal structure of Al75Fe15Ni10.


2005 ◽  
Vol 19 (03) ◽  
pp. 85-98 ◽  
Author(s):  
S. BELLUCCI

One of the main involvements of the INFN-Laboratori Nazionali di Frascati group in channeling researches is described, i.e. the crystal undulator R & D, with the characterization of the crystal undulator prototypes with SEM and the positron beam. We consider a precise determination of the optimal experimental conditions for channeling of this kind of accelerated particles through such microstructured crystals, as promising candidates for producing X-ray beams.


1985 ◽  
Vol 57 ◽  
Author(s):  
W. K. Warburton ◽  
K. F. Ludwig ◽  
L. Wilson ◽  
A. Bienenstock

AbstractThe differential anomalous scattering technique is outlined and compared to other techniques for studying short-range order in amorphous systems, such as EXAFS. The differential distribution functions obtained for liquid GeBr4 were found to support a model for the liquid state based on the structure of the h.c.p. crystal. Application of the technique to aqueous ZnBr2 also allowed discr imination between structural models.


2000 ◽  
Vol 113 (20) ◽  
pp. 9149-9161 ◽  
Author(s):  
Jon M. Sorenson ◽  
Greg Hura ◽  
Robert M. Glaeser ◽  
Teresa Head-Gordon

1987 ◽  
Vol 42 (4) ◽  
pp. 367-376 ◽  
Author(s):  
Yusuke Tamura ◽  
Isao Okada ◽  
Hitoshi Ohtaki ◽  
Toshio Yamaguchi

X-Ray scattering measurements of 2.78 and 5.56 molal aqueous solutions of caesium iodide and 2.78 and 6.05 molal lithium iodide were carried out at 293 and 343 K Differences in the radial distribution functions (DRDFs) have been obtained between the caesium iodide and lithium iodide solutions of similar composition, the latter being taken as a reference for the data analysis of the former. The DRDFs show a peak arising from Cs - I contact-ion-pairs at 390 pm for all the caesium iodide solutions. The hydration structure of the caesium and iodide ions has been revealed. Effects of the concentration and temperature on the formation of ion-pairs and on the hydration structure of the ions are discussed


1989 ◽  
Vol 44 (9) ◽  
pp. 814-820 ◽  
Author(s):  
E. Matsubara ◽  
Y. Waseda ◽  
A. Inoue ◽  
T. Masumoto ◽  

Abstract The structure of a new amorphous Al87Y8Ni5, indicating high strength and good ductility, was studied by anomalous X-ray scattering (AXS). For comparison, a binary amorphous Al90Y10 alloy was also investigated. The environmental radial distribution functions around Y and Ni as well as the ordinary RDF in the ternary alloy, and the environmental RDF around Y and the ordinary RDF in the binary alloy were determined. From the analysis of these RDFs it is found that the Y atoms are completely surrounded by Al in the binary alloy, and that some of these Al atoms are replaced by Ni atoms in the ternary alloy.


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