X-ray Diffraction Analysis of NdCl3 Melt

Abstract The structure of molten NdClj at 800 CC has been investigated by X-ray scattering and the correlation method. The nearest neighbor distance and coordination number of Nd-Cl are 2.77 Ä and 5.5 A, respectively. The Nd-Nd and CI-CI distances are 5.08 and 4.04 Ä, respectively. The average nearest neighbor distance and coordination number decrease markedly on melting, and the resulting short range structure of the melt is approximately octahedral

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Density and Packing in Uranium Based Metallic Glasses

MRS Proceedings ◽

10.1557/proc-57-283 ◽

1985 ◽

Vol 57 ◽

Cited By ~ 1

Author(s):

A. J. Drehman

Keyword(s):

Metallic Glasses ◽

Excess Volume ◽

Nearest Neighbor ◽

Glass Composition ◽

Neighbor Distance ◽

Compositional Dependence ◽

X Ray Diffraction ◽

X Ray ◽

Wide Compositional Range ◽

Nearest Neighbor Distance

AbstractDensity and x-ray diffraction measurements were performed over a wide compositional range of U-Fe and U-Co metallic glass ribbons. The compositional dependence of both the density and the average nearest neighbor distance exhibits a change in slope at approximately 28 at.% transition metal. This suggests an “ideal” glass composition possessing a minimum excess volume. A qualitative model of atomic packing is proposed, which is based on the compositional dependence of the atomic volume and nearest neighbor distance.

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X-Ray Diffraction Study on the Local Structure of Molten ErCl3

Zeitschrift für Naturforschung A ◽

10.1515/zna-1994-7-814 ◽

1994 ◽

Vol 49 (7-8) ◽

pp. 811-814 ◽

Cited By ~ 20

Author(s):

Yasuhiko Iwadate ◽

Takuma Iida ◽

Kazuko Fukushima ◽

Junichi Mochinaga ◽

Marcelle Gaune-Escard

Keyword(s):

Diffraction Study ◽

Coordination Number ◽

Local Structure ◽

Short Range ◽

Octahedral Geometry ◽

Nearest Neighbour ◽

X Ray Diffraction ◽

Neighbour Distance ◽

X Ray ◽

Short Range Structure

Abstract The short range structure of molten ErCl3 at 1053 K was investigated by X-ray diffraction. The nearest neighbour distance of Er3+-Cl- and the coordination number of Cl- around Er3+ were estimated to be 2.63 Å and 5.8 Å, respectively, and the Er3+-Er3+ and Cl--Cl- distances 4.05 Å and 3.75 Å, respectively. The ratio of the anion-anion pair distance to the cation-anion pair distance (r--/r+-) was, therefore, 1.43, being close to 1.41, characteristic of octahedral geometry. These results indicate that ErCl63--octahedra exist in molten ErCl3. Probably Er2Clio and a small amount of Er2Cl115- ions are formed according to the geometrical calculations of bond lengths and bond angles.

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Local Atomic Structures in Amorphous and Quasicrystalline Zr70Ni10Pt20and Zr80Pt20Alloys by the Anomalous X-ray Scattering Method

MRS Proceedings ◽

10.1557/proc-644-l1.1 ◽

2000 ◽

Vol 644 ◽

Cited By ~ 2

Author(s):

Eiichiro Matsubara ◽

Takahiro Nakamura ◽

Masaki Sakurai ◽

Muneyuki Imafuku ◽

Shigeo Sato ◽

...

Keyword(s):

Short Range ◽

Short Range Order ◽

Nearest Neighbor ◽

Scattering Method ◽

X Ray ◽

Coordination Numbers ◽

Atomic Structures ◽

X Ray Scattering ◽

Icosahedral Clusters ◽

Ray Scattering

AbstractLocal atomic structures around Zr and Pt in a quasicrystalline Zr80Pt20alloy, and amorphous and quasicrystalline Zr70Ni10Pt20alloys have been determined by the anomalous x-ray scattering (AXS) method. A distinct prepeak observed in an intensity profile of the amorphous Zr70Ni10Pt20alloy indicates existence of strong chemical short-range order (CSRO) clusters in the amorphous phase. Total coordination numbers around Zr and Pt in a nearest neighbor region in both alloys have been evaluated. The values around Pt are almost equal to 12 in the amorphous and quasicrystalline states suggest formation of icosahedral clusters around Pt. Some of crystalline structures formed from the quasicrystalline phases by annealing consist of icosahedral clusters of Zr and Ni atoms, or polyhedral clusters of Zr and Pt atoms similar with icosahedral clusters. The present result appears to support that the phase transformation from the amorphous to the crystal through the quasicrystal is explained by the icosahedral CSRO clusters in the amorphous and quasicrystalline states.

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X-ray diffraction study on the short-range structure of K2O–TeO2 glasses and melts

Journal of Alloys and Compounds ◽

10.1016/s0925-8388(00)01080-x ◽

2000 ◽

Vol 311 (2) ◽

pp. 153-158 ◽

Cited By ~ 7

Author(s):

Yasuhiko Iwadate ◽

Takeshi Mori ◽

Takeo Hattori ◽

Shin Nishiyama ◽

Kazuko Fukushima ◽

...

Keyword(s):

Diffraction Study ◽

Short Range ◽

X Ray Diffraction ◽

X Ray ◽

Short Range Structure

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ChemInform Abstract: X-Ray Diffraction and Raman Spectroscopic Study on the Short-Range Structure of Molten CeCl3

ChemInform ◽

10.1002/chin.199323010 ◽

2010 ◽

Vol 24 (23) ◽

pp. no-no

Author(s):

J. MOCHINAGA ◽

M. IKEDA ◽

K. IGARASHI ◽

K. FUKUSHIMA ◽

Y. IWADATE

Keyword(s):

Spectroscopic Study ◽

Short Range ◽

X Ray Diffraction ◽

X Ray ◽

Raman Spectroscopic ◽

Raman Spectroscopic Study ◽

Short Range Structure

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X-ray diffraction and Raman spectroscopic study on the short-range structure of molten CeCl3

Journal of Alloys and Compounds ◽

10.1016/0925-8388(93)90302-4 ◽

1993 ◽

Vol 193 (1-2) ◽

pp. 36-37 ◽

Cited By ~ 24

Author(s):

J. Mochinaga ◽

M. Ikeda ◽

K. Igarashi ◽

K. Fukushima ◽

Y. Iwadate

Keyword(s):

Spectroscopic Study ◽

Short Range ◽

X Ray Diffraction ◽

X Ray ◽

Raman Spectroscopic ◽

Raman Spectroscopic Study ◽

Short Range Structure

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Nanocrystalline Solid Solutions of Cu/Co and Other Novel Nanomaterials

MRS Proceedings ◽

10.1557/proc-457-261 ◽

1996 ◽

Vol 457 ◽

Author(s):

A. S. Edelstein ◽

V. G. Harris ◽

D. Rolison ◽

J. H. Perepezko ◽

D. Smith

Keyword(s):

Heat Treatment ◽

Lattice Constant ◽

Solid Solutions ◽

Nearest Neighbor ◽

Neighbor Distance ◽

X Ray Diffraction ◽

X Ray ◽

Vegard’S Law ◽

Minimum Heat ◽

Special Case

ABSTRACTA brief review will be given of the preparation, synthesis and properties of the Cu/Co system. The special case of the synthesis of nanocrystalline Cu.80Co.20 by precipitation and reduction of hydroxides is discussed in more detail. It was found that the lattice constant of nanocrystalline Cu.80Co.20. determined from x-ray diffraction measurements, approximately fits Vegard's Law and the average nearest neighbor distance from both the Cu and Co atoms, determined from EXAFS measurements, ir shifted from their bulk values. Samples given the minimum heat treatment needed to reduce the hydroxides contained Co-rich regions. Heat treatments cause the Co to segregate preferentially onto the surface of the Cu crystals. The presence of the Co delays the oxidation of the Cu surfaces.

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Short-range structure of a multicomponent glass by an X-ray diffraction method

Journal of Materials Science Letters ◽

10.1007/bf00723796 ◽

1988 ◽

Vol 7 (8) ◽

pp. 891-892 ◽

Cited By ~ 4

Author(s):

Takeo Hattori ◽

Yasuhiko Iwadate ◽

Kaxuo Igarashi ◽

Junichi Mochinaga

Keyword(s):

Short Range ◽

Diffraction Method ◽

X Ray Diffraction ◽

X Ray ◽

Multicomponent Glass ◽

Short Range Structure

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Observations of coexistence of FCC and HCP phases in C60 by HREM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100120953 ◽

1992 ◽

Vol 50 (1) ◽

pp. 110-111

Author(s):

Z.G. Li ◽

Paul J. Fagan

Keyword(s):

Carbon Atom ◽

Crystalline Structure ◽

Diffraction Data ◽

Large Scale ◽

Nearest Neighbor ◽

Neighbor Distance ◽

X Ray Diffraction ◽

X Ray ◽

Hexagonal Close Packed ◽

Correct Structure

Since the discovery of a large scale synthesis of fullerenes there has been intense interest in the structure of these materials. The first diffraction data suggested that crystalline C60 had a hexagonal close-packed (hep) structure with a nearest neighbor distance of 10.04 Å. The possibility of a disordered stacking of C60 molecules was first noted in this study. Since then, there has been some confusion regarding the exact crystalline structure of C60 as determined by electron and X-ray diffraction. In particular, a diffraction feature corresponding to a spacing of 8.7 Å has been noted in several studies. Recendy there had been a growing consensus that fcc is the correct structure for sublimed C60. Although the internal carbon atom arrangement of the C60 molecules cannot be determined, the actual packing and defects in C60 crystals over small and relatively large regions are readily seen by HRTEM. We have found by direct imaging a relatively large region of defect-free hep packing of C60 spheres sublimed onto a relatively cool microscopy grid.

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