Electron Diffraction with the Amorphous Alloys Fe80B20 and Mn73Si27

Electron diffraction with amorphous Fe80B20 and Mn73Si27 yields structure factors and pair correlation functions which are discussed together with the results of X-ray- and neutron-diffraction experiments. For Mn73Si27 additional interesting details are revealed. A tetrahedral model for Mn73Si27 is described. Finally we show that the evaluation of partial structure factors by the three beam experiment, i.e. the combination of an electron-, X-ray- and neutron-diffraction experiment is not possible in general.

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Evaluation of the Structure of Amorphous Tungsten Oxide W28O72 by the Combination of Electron-, X-Ray- and Neutron-Diffraction (Three-Beam Experiment)

Zeitschrift für Naturforschung A ◽

10.1515/zna-2006-3-412 ◽

2006 ◽

Vol 61 (3-4) ◽

pp. 189-196 ◽

Cited By ~ 1

Author(s):

Jürgen Ankele ◽

Joachim Mayer ◽

Peter Lamparter ◽

Siegfried Steeb

Keyword(s):

Neutron Diffraction ◽

Diffraction Data ◽

Structural Model ◽

Pair Correlation ◽

Electron Diffraction Data ◽

X Ray ◽

Structure Factors ◽

Beam Experiment ◽

Reverse Monte Carlo Simulation ◽

Sputter Deposited

From the combination of quantitative electron-diffraction data with X-ray- and neutron-diffraction data (so-called three-beam experiment) the partial structure factors and pair correlation functions of amorphous sputter deposited W28O72 were determined. On the basis of the experimental atomic distances and coordination numbers, and by comparison with crystalline WO3, a structural model was developed, which consists of twisted WO6 octahedra. Reverse Monte Carlo simulation in accordance with the experimental data was performed to verify the results

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Neutron Diffraction with the Metallic Glass Ni31Dy69 ( + 10 a/o D) Using Isotopic Substitution

Zeitschrift für Naturforschung A ◽

10.1515/zna-1985-0214 ◽

1985 ◽

Vol 40 (2) ◽

pp. 191-192

Author(s):

A. Wildermuth ◽

P. Lamparter ◽

S. Steeb

Keyword(s):

Amorphous Alloy ◽

Neutron Diffraction ◽

Metallic Glass ◽

Structure Factor ◽

Isotopic Substitution ◽

Diffraction Experiment ◽

Partial Structure ◽

Neutron Diffraction Experiment ◽

Partial Structure Factor ◽

Structure Factors

By neutron diffraction using the method of isotopic substitution with the amorphous alloy Ni31Dy69 the partial structure factors SNiNi, SDyDy and SNiDy were obtained, furthermore with the same specimen containing 10 a/o deuterium a partial structure factor SDD resulted. For the evaluation of SDD it was necessary to perform the neutron diffraction experiment with an alloy whose both components were zero scattering isotopic mixtures of Ni or Dy, respectively.

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X-Ray and Neutron Diffraction of Amorphous Nickel-Zirconium-Alloys as Prepared in Different Ways

Zeitschrift für Naturforschung A ◽

10.1515/zna-1991-0604 ◽

1991 ◽

Vol 46 (6) ◽

pp. 491-498 ◽

Cited By ~ 1

Author(s):

L. Schultz ◽

P. Lamparter ◽

S. Steeb

Keyword(s):

Neutron Diffraction ◽

Short Range ◽

Melt Spinning ◽

Short Range Order ◽

Pair Correlation ◽

Zirconium Alloys ◽

X Ray ◽

Coordination Numbers ◽

Structure Factors ◽

The One

AbstractThe structure of amorphous NiχZr100-χ-alloys (Χ= 30, 31, 34, 63.7, and 65), which were produced by melt spinning (MS), mechanical alloying (MA), and sputtering (SP) was studied by X-ray- and neutron diffraction yielding structure factors, pair correlation functions, coordination numbers, atomic distances, and Warren-Cowley chemical short range order parameters. The atomic arrangement within the first coordination sphere is independent of the method of preparation while in the second and higher spheres it differs between the MS- and the MA-alloys on the one side and the SP-specimens on the other side. Thus one understands that some physical properties of the different specimens differ

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Semi-Empirical Fitting of Partial Pair Correlation Functions of Amorphous Alloys

Zeitschrift für Naturforschung A ◽

10.1515/zna-1995-1227 ◽

1995 ◽

Vol 50 (12) ◽

pp. 1205-1218

Author(s):

E. Sváb ◽

F. Hajdu ◽

Gy. Mészáros

Keyword(s):

Amorphous Alloys ◽

Structural Parameters ◽

Pair Correlation ◽

Analytical Formula ◽

Partial Structure ◽

Fitting Procedure ◽

Atomic Pair ◽

Structure Factors ◽

Characteristic Features ◽

Semi Empirical

Abstract A semi-empirical fitting procedure has been developed and used in analysing the characteristic features of the partial structure factors of binary amorphous alloys. An analytical formula is given to fit the experimental atomic pair correlation function as a sum of Gaussians. The inverse Fourier transform of the fitted terms reproduces all features of the experimental structure function. In addition to the structural parameters, the modelling gives a quantitative explanation for the complex origin of characteristic features in the diffraction pattern such as pre-peak, pre-minimum, and split peaks in the partial structure factor.

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Combination of X-Ray and Neutron Diffraction for Determination of Partial Pair Correlation Functions of Amorphous Alloys: A New Approach

Materials Science Forum ◽

10.4028/www.scientific.net/msf.321-324.282 ◽

2000 ◽

Vol 321-324 ◽

pp. 282-289 ◽

Cited By ~ 1

Author(s):

A.F. Sidorenko ◽

Yu.A. Babanov ◽

D. Raoux ◽

S. Lefebvre

Keyword(s):

Neutron Diffraction ◽

Correlation Functions ◽

Amorphous Alloys ◽

Pair Correlation ◽

New Approach ◽

Pair Correlation Functions ◽

X Ray

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X-ray- and Neutron-diffraction Studies with Quasicrystalline and Amorphous Al-V- and Al-Mn-alloys

Zeitschrift für Naturforschung A ◽

10.1515/zna-1990-0507 ◽

1990 ◽

Vol 45 (5) ◽

pp. 627-638

Author(s):

S. Seehafer ◽

P. Lamparter ◽

S. Steeb

Keyword(s):

Neutron Diffraction ◽

Coordination Number ◽

Correlation Functions ◽

Melt Spinning ◽

Pair Correlation ◽

Partial Density ◽

Isomorphous Substitution ◽

Hard Sphere Model ◽

X Ray ◽

Structure Factors

Abstract Amorphous and quasicrystalline samples of Al84Mn16 and Al84V16 were produced by sputtering and melt-spinning, respectively. From X-ray and neutron-diffraction-results the total structure factors were evaluated. For amorphous as well as for quasicrystalline Al84V16 the partial SAl-Al- and SAl-V-structure factors were obtained, which yield the corresponding partial pair correlation functions, the atomic distances, and the partial coordination numbers. Also some information concerning the partial Bhatia-Thornton correlation functions could be obtained. Both the amorphous and the quasicrystalline Al-V-alloys show a linear expansion by a factor of 1.03 compared to the corresponding Al-Mn-alloy. The two amorphous alloys can be designed as isomorphous, whereas the quasicrystalline ones show pronounced deviations in the distance between unequal atoms. The shortest atomic distance in amorphous Al84V16 is 2.69 A, being,formed by Al-V-pairs with a coordination number 2. The nearest Al-Al-distance amounts to 2.84 A with a coordination number 8. The partial density-concentration correlation function clearly deviates from the hard sphere model. With the quasicrystalline specimens, the isomorphous substitution of Mn- and V-atoms is not perfect. The Al-V-correlation is split up, and this is not observed for the Al-Mn-correlation. Comparison of the amorphous and the corresponding quasicrystalline alloy shows some similarities

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Consistent partial structure factors for amorphousNi0.33(ZryHf1−y)0.67using x-ray and neutron diffraction

Physical Review B ◽

10.1103/physrevb.53.8983 ◽

1996 ◽

Vol 53 (14) ◽

pp. 8983-8992 ◽

Cited By ~ 8

Author(s):

Yan Xu ◽

W. B. Muir ◽

Z. Altounian ◽

W. J. L. Buyers ◽

R. L. Donaberger

Keyword(s):

Neutron Diffraction ◽

Partial Structure ◽

X Ray ◽

Structure Factors

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Neutron diffraction experiment with the Y116S variant of transthyretin using iBIX at J-PARC: application of a new integration method

Acta Crystallographica Section D Structural Biology ◽

10.1107/s2059798320012498 ◽

2020 ◽

Vol 76 (11) ◽

pp. 1050-1056

Author(s):

Katsuhiro Kusaka ◽

Takeshi Yokoyama ◽

Taro Yamada ◽

Naomine Yano ◽

Ichiro Tanaka ◽

...

Keyword(s):

Neutron Diffraction ◽

Diffraction Data ◽

Amyloid Fibrils ◽

Integration Method ◽

Proton Accelerator ◽

Diffraction Experiment ◽

Wild Type ◽

Neutron Diffraction Experiment ◽

X Ray ◽

Attr Amyloidosis

Transthyretin (TTR) is one of more than 30 amyloidogenic proteins, and the amyloid fibrils found in patients afflicted with ATTR amyloidosis are composed of this protein. Wild-type TTR amyloids accumulate in the heart in senile systemic amyloidosis (SSA). ATTR amyloidosis occurs at a much younger age than SSA, and the affected individuals carry a TTR mutant. The naturally occurring amyloidogenic Y116S TTR variant forms more amyloid fibrils than wild-type TTR. Thus, the Y116S mutation reduces the stability of the TTR structure. A neutron diffraction experiment on Y116S TTR was performed to elucidate the mechanism of the changes in structural stability between Y116S variant and wild-type TTR through structural comparison. Large crystals of the Y116S variant were grown under optimal crystallization conditions, and a single 2.4 mm3 crystal was ultimately obtained. This crystal was subjected to time-of-flight (TOF) neutron diffraction using the IBARAKI biological crystal diffractometer (iBIX) at the Japan Proton Accelerator Research Complex, Tokai, Japan (J-PARC). A full data set for neutron structure analysis was obtained in 14 days at an operational accelerator power of 500 kW. A new integration method was developed and showed improved data statistics; the new method was applied to the reduction of the TOF diffraction data from the Y116S variant. Data reduction was completed and the integrated intensities of the Bragg reflections were obtained at 1.9 Å resolution for structure refinement. Moreover, X-ray diffraction data at 1.4 Å resolution were obtained for joint neutron–X-ray refinement.

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