A comparison of structural relaxation in Ni64B36 and Fe83B17 metallic glasses

1986 ◽  
Vol 64 (6) ◽  
pp. 658-664 ◽  
Author(s):  
K. Dini ◽  
N. Cowlam ◽  
G. P. Gregan ◽  
H. A. Davies
Keyword(s):  
Low Temperature ◽  
Transition Metal ◽  
Neutron Diffraction ◽  
Metallic Glasses ◽  
Structural Relaxation ◽  
Structural Changes ◽  
Structural Models ◽  
Density Measurements ◽  
X Ray ◽  
Low Temperature Annealing

An investigation has been made of the structural changes that accompany low-temperature annealing (structural relaxations) in two different metallic glasses using X-ray and neutron diffraction, calorimetry, and density measurements. The structure of Fe83B17 having the archetypal composition of transition-metal – metalloid glasses appears to be more susceptible to structural relaxation than Ni64B36 glass with a higher metalloid content. This behaviour is reflected in the smaller enthalpy of relaxation of the Ni64B36 glass. The structural changes observed are discussed in terms of current structural models.

Structural Changes in Amorphous Silicon Annealed at Low Temperatures

2001 ◽  
Vol 664 ◽  
Author(s):  
Branko Pivac ◽  
Pavo Dubček ◽  
Ognjen Milat ◽  
Ivan Zulim
Keyword(s):  
Low Temperature ◽  
Amorphous Silicon ◽  
Structural Properties ◽  
Low Temperatures ◽  
Structural Changes ◽  
Void Size ◽  
Dangling Bonds ◽  
X Ray ◽  
Low Temperature Annealing ◽  
Hydrogen Dilution

ABSTRACTThe hydrogen dilution in the course of production of amorphous silicon (a-Si) influences its structural properties, which affect significantly light-induced degradation. We used FTIR, X-ray reflectivity and GISAXS analysis to monitor the structural changes occurring during the low temperature annealing of undoped a-Si:H films. FTIR results show that upon annealing at very low temperatures, hydrogen is moved from its positions (voids) where it was accumulated unbonded to silicon and is subsequently trapped at dangling bonds, enhancing disorder. X-ray reflectivity and GISAXS measurements confirmed the enhancement of the void size.

Low-Temperature Annealing of the X-Ray-Induced Volume Expansion and Coloration of LiF

1964 ◽  
Vol 134 (2A) ◽  
pp. A485-A491 ◽  
Author(s):  
S. Mascarenhas ◽  
D. A. Wiegand ◽  
R. Smoluchowski
Keyword(s):  
Low Temperature ◽  
Volume Expansion ◽  
X Ray ◽  
Low Temperature Annealing

The structure of oxide glasses studied by high-energy x-ray diffraction

2020 ◽  
Vol 61 (6) ◽  
pp. 233-238
Author(s):  
S. Kohara ◽  
◽  
N. Umesaki ◽  
H. Ohno ◽  
K. Suzuya ◽  
...  
Keyword(s):  
Neutron Diffraction ◽  
Structural Information ◽  
Structural Models ◽  
High Energy ◽  
Reverse Monte Carlo ◽  
Oxide Glasses ◽  
Neutron Diffraction Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Approaches To Study

The use of high‑energy x‑ray diffraction techniques with the latest generation synchrotron sources has created new approaches to study quantitatively the structure of noncrystalline materials. Recently, this technique has been combined with neutron diffraction at pulsed source to provide more detailed and reliable structural information not previously available. This article reviews and summarises recent results obtained from the high energy x‑ray diffraction on several oxide glasses, SiO2, B2O3 and PbSiO3, using bending magnet beamlines at SPring‑8. In particular, it addresses the structural models of the oxide glasses obtained by the reverse Monte Carlo (RMC) modelling technique using both the high energy x‑ray and neutron diffraction data.

scholarly journals Single-crystal neutron diffraction study of β-Cs3(HSO4)2[H2−x (S x P1−x )O4] (x ≃ 0.5) at 15 K

1999 ◽  
Vol 55 (3) ◽  
pp. 285-296 ◽  
Author(s):  
S. M. Haile ◽  
W. T. Klooster
Keyword(s):  
Neutron Diffraction ◽  
Single Crystal ◽  
Local Structure ◽  
Unit Cell Volume ◽  
Structural Models ◽  
Neutron Diffraction Study ◽  
Unit Cell ◽  
Asymmetric Unit ◽  
X Ray ◽  
Anisotropic Displacement Parameters

The structure of β-Cs3(HSO4)2[H2−x (S x P1−x )O4] has been examined by single-crystal neutron diffraction at 15 K. The compound crystallizes in space group C2/c and contains four formula units in the unit cell, with lattice parameters a = 19.769 (9), b = 7.685 (2), c = 8.858 (3) Å and β = 100.60 (4)°. Refinement of P, S and H site occupancies indicated that the value of x (in the stoichiometry) is 0.500 (6). This, together with the unit-cell volume of 1322.8 (14) Å3, implies a density of 3.463 Mg m−3. The structure contains zigzag rows of XO4 anions, where X = P or S, that alternate, in a checkerboard fashion, with zigzag rows of Cs cations. Moreover, there is one proton site, H(3), with an occupancy of 0.25 and one X-atom site, X(1), that is occupied by 0.5 P and 0.5 S. These features are in general agreement with a previous X-ray structure determination carried out at 298 K. In contrast to the X-ray study, however, it was found that two different structural models adequately fit the diffraction data. In the first model, the proton vacancies and the P atoms were assumed to be randomly distributed over the H(3) and X(1) sites, respectively, and to have no impact on the local structure. In the second model, several atoms were assigned split occupancies over two neighboring sites, to reflect the presence or absence of a proton vacancy, and the presence of P or S on the X(1) site. Refinement assuming the first model, in which anisotropic displacement parameters for 12 of 14 atom sites in the asymmetric unit were employed, yielded residuals w R(F 2) = 0.084 and w R(F) = 0.038. For the second model, in which anisotropic displacement parameters were utilized for only the five atoms that were not split relative to the first model, the residuals were w R(F 2) = 0.081 and w R(F) = 0.036.

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