scholarly journals The structure of deuterated benzene films adsorbed on the graphite (0001) basal plane: what happens below and above the monolayer coverage?

2014 ◽  
Vol 16 (40) ◽  
pp. 22116-22121 ◽  
Author(s):  
Emanuel Bahn ◽  
Holly Hedgeland ◽  
Andrew P. Jardine ◽  
Paul F. Henry ◽  
Thomas C. Hansen ◽  
...  
Keyword(s):  
Neutron Scattering ◽  
Structure Formation ◽  
Basal Plane ◽  
Detailed Picture ◽  
Monolayer Coverage ◽  
Deuterated Benzene

Neutron scattering gives a detailed picture of structure formation in thin benzene films overturning existing models.

Neutron scattering study of nitrogen adsorbed on basal-plane-oriented graphite

1976 ◽  
Vol 13 (4) ◽  
pp. 1446-1462 ◽  
Author(s):  
J. K. Kjems ◽  
L. Passell ◽  
H. Taub ◽  
J. G. Dash ◽  
A. D. Novaco
Keyword(s):  
Neutron Scattering ◽  
Basal Plane ◽  
Scattering Study ◽  
Neutron Scattering Study

Neutron-Scattering Studies of the Structure and Dynamics ofAr36Monolayer Films Adsorbed on Basal-Plane-Oriented Graphite

1975 ◽  
Vol 34 (11) ◽  
pp. 654-657 ◽  
Author(s):  
H. Taub ◽  
L. Passell ◽  
J. K. Kjems ◽  
K. Carneiro ◽  
J. P. McTague ◽  
...  
Keyword(s):  
Neutron Scattering ◽  
Basal Plane ◽  
Structure And Dynamics

Neutron Scattering from Nitrogen Adsorbed on Basal-Plane-Oriented Graphite

1974 ◽  
Vol 32 (13) ◽  
pp. 724-727 ◽  
Author(s):  
J. K. Kjems ◽  
L. Passell ◽  
H. Taub ◽  
J. G. Dash
Keyword(s):  
Neutron Scattering ◽  
Basal Plane

Intercalate Phonon Densities of States for Alkali-Graphite Compounds

1982 ◽  
Vol 20 ◽  
Author(s):  
W. A. Kamitakahara ◽  
H. Zabel
Keyword(s):  
Neutron Scattering ◽  
Temperature Dependence ◽  
Basal Plane ◽  
Densities Of States

ABSTRACTNeutron scattering methods have been used to determine the partial phonon densities of states gM(ν) for inplane vibrations of M atoms in MCx compounds, where M = K, Rb or Cs, and x = 8, 24, 36. Only modes with both phonon wave vectors and displacements in the basal plane are represented in gM(ν). Detailed measurements of the temperature dependence were made for RbC24 and KC24, in order to study the influence of the order-disorder transformations in these compounds. The results are interpreted in terms of different pictures of the disordered state.

Observations of the Thermal Decomposition of Brucite

1968 ◽  
Vol 26 ◽  
pp. 446-447
Author(s):  
P. L. Burnett ◽  
W. R. Mitchell ◽  
C. L. Houck
Keyword(s):  
Thermal Decomposition ◽  
Magnesium Oxide ◽  
Basal Plane ◽  
Magnesium Ions ◽  
A Value ◽  
Reaction Proceeds

Natural Brucite (Mg(OH)2) decomposes on heating to form magnesium oxide (MgO) having its cubic ﹛110﹜ and ﹛111﹜ planes respectively parallel to the prism and basal planes of the hexagonal brucite lattice. Although the crystal-lographic relation between the parent brucite crystal and the resulting mag-nesium oxide crystallites is well known, the exact mechanism by which the reaction proceeds is still a matter of controversy. Goodman described the decomposition as an initial shrinkage in the brucite basal plane allowing magnesium ions to shift their original sites to the required magnesium oxide positions followed by a collapse of the planes along the original <0001> direction of the brucite crystal. He noted that the (110) diffraction spots of brucite immediately shifted to the positions required for the (220) reflections of magnesium oxide. Gordon observed separate diffraction spots for the (110) brucite and (220) magnesium oxide planes. The positions of the (110) and (100) brucite never changed but only diminished in intensity while the (220) planes of magnesium shifted from a value larger than the listed ASTM d spacing to the predicted value as the decomposition progressed.

The stability of dislocation networks under various oxygen-doping conditions in superconducting Bi2Sr2CaCu2Oy single crystals and their influence on the flux pinning properties

1994 ◽  
Vol 52 ◽  
pp. 802-803
Author(s):  
Y. Feng ◽  
X. Y. Cai ◽  
R. J. Kelley ◽  
D. C. Larbalestier
Keyword(s):  
Single Crystals ◽  
Oxygen Content ◽  
Basal Plane ◽  
Flux Pinning ◽  
Pinning Centers ◽  
Before And After ◽  
Anomalous Peak ◽  
Basal Plane Dislocation ◽  
The Stability ◽  
Further Development

The issue of strong flux pinning is crucial to the further development of high critical current density Bi-Sr-Ca-Cu-O (BSCCO) superconductors in conductor-like applications, yet the pinning mechanisms are still much debated. Anomalous peaks in the M-H (magnetization vs. magnetic field) loops are commonly observed in Bi2Sr2CaCu2Oy (Bi-2212) single crystals. Oxygen vacancies may be effective flux pinning centers in BSCCO, as has been found in YBCO. However, it has also been proposed that basal-plane dislocation networks also act as effective pinning centers. Yang et al. proposed that the characteristic scale of the basal-plane dislocation networksmay strongly depend on oxygen content and the anomalous peak in the M-H loop at ˜20-30K may be due tothe flux pinning of decoupled two-dimensional pancake vortices by the dislocation networks. In light of this, we have performed an insitu observation on the dislocation networks precisely at the same region before and after annealing in air, vacuumand oxygen, in order to verify whether the dislocation networks change with varying oxygen content Inall cases, we have not found any noticeable changes in dislocation structure, regardless of the drastic changes in Tc and the anomalous magnetization. Therefore, it does not appear that the anomalous peak in the M-H loops is controlled by the basal-plane dislocation networks.

Local atomic structure of relaxor ferroelectric solids studied by pulsed neutron scattering

1994 ◽  
Vol 52 ◽  
pp. 554-555
Author(s):  
T. Egami ◽  
H. D. Rosenfeld ◽  
S. Teslic
Keyword(s):  
Neutron Scattering ◽  
Atomic Structure ◽  
Argonne National Laboratory ◽  
Relaxor Ferroelectrics ◽  
Relaxor Ferroelectric ◽  
Crystallographic Structure ◽  
Chemical Inhomogeneity ◽  
Distribution Analysis ◽  
Ferroelectric Transition ◽  
Pulsed Neutron

Relaxor ferroelectrics, such as Pb(Mg1/3Nb2/3)O3 (PMN) or (Pb·88La ·12)(Zr·65Ti·35)O3 (PLZT), show diffuse ferroelectric transition which depends upon frequency of the a.c. field. In spite of their wide use in various applications details of their atomic structure and the mechanism of relaxor ferroelectric transition are not sufficiently understood. While their crystallographic structure is cubic perovskite, ABO3, their thermal factors (apparent amplitude of thermal vibration) is quite large, suggesting local displacive disorder due to heterovalent ion mixing. Electron microscopy suggests nano-scale structural as well as chemical inhomogeneity.We have studied the atomic structure of these solids by pulsed neutron scattering using the atomic pair-distribution analysis. The measurements were made at the Intense Pulsed Neutron Source (IPNS) of Argonne National Laboratory. Pulsed neutrons are produced by a pulsed proton beam accelerated to 750 MeV hitting a uranium target at a rate of 30 Hz. Even after moderation by a liquid methane moderator high flux of epithermal neutrons with energies ranging up to few eV’s remain.

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