Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-23T11:38:00.689Z Has data issue: false hasContentIssue false
  • English
  • Français

Photon Scattering from Single Crystals

Published online by Cambridge University Press:  06 March 2019

Charles S. Barrett
Charles S. Barrett*
Affiliation:
The University of Chicago, Chicago, Illinois
Get access

Abstract

Protons and other energetic particles when back-scattered from a single crystal emerge with anisotropic Intensity distributions. There are minima In the intensities along crystallographic directions and planes. The indices of these directions and planes and the relative intensities of these crystallographic features can be readily established by photographing the pattern of emerging particles. The patterns disclose the symmetry of the scatterer but cannot be expected to reveal the presence or absence of a symmetry center, so that the symmetry of a pattern should be related to the symmetry of one of the 11 Laue-symmetry groups, Photographs made with 50-150 keV protons are found to differ not only for crystals that belong to different Laue groups, but also for crystals belonging to the same Laue group but having different space lattices. The patterns reveal a limited amount of structural information including information on orientation, crystal perfection, and axial ratios, but not unit cell dimensions, The interpretation of patterns on the basis of particle trajectories has had major successes in the past; interpretation on the basis of diffraction has also been proposed but the inherent complexities associated, with this are very severe. Some intensity relationships observed for various crystals a-re presented, and highly simplified approximate ways of predicting relative intensities of lines are compared with the observations.

Type
Research Article
Information
Advances in X-Ray Analysis , Volume 12: Seventeenth Annual Conference on Applications of X-ray Analysis, August 21-23, 1968 , 1968 , pp. 72 - 86
Copyright
Copyright © International Centre for Diffraction Data 1968

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Gemmell, D. S. and Holland, R. E., “Blocking Effects in the Emergence of Charged Partials from Single Crystals,” Phys. Rev. Letters 14, 945 (1965).Google Scholar
2. Datz, S., Erginsoy, C., Leibfried, G. and Lutz, H. O., “Motion of Energetic Partials in Crystals,” Annual Review of Nuclear Science, 1968, p. 129.Google Scholar
3. Tulinov, A. F., “Influence of the Crystal Lattice on Some Atomic and Nuclear Processes,” Soviet Phys. Usp. 8, 86k (1966).Google Scholar
4. Barrett, C. S., Mueller, R. M. and White, W., “Proton Blocking in Cubic Crystals, “ J. Appl. Physics, in press.Google Scholar
5. Lindhard, J., “Motion of Swift Charged Partials , as Influenced by Strings of Atoms in Crystals,” Phys. Letters 12, 126 (1964).Google Scholar
6. Lindhard, J., “Influence of Crystal Lattice on Motion of Energetic Charged Partials , “ Matematisk-fysiske Meddelelser Ret Kongelige Danski Videnskabernes Selskab 34, 1 (1965).Google Scholar
7. Lervig, P., Lindhard, J. and Nielson, V., “Quantal Treatment of Directional Effects for Energetic Charged Partials in Crystal Lattices,” Nuclear Physics A96, 481 (1967).Google Scholar
8. Chadderton, L. T., “Wave/Particle Duality in Proton Channeling in Crystals,” Phys. Letters 23, 303 (1966).Google Scholar
9. DeWames, R. E., Hall, W. F. and Chadderton, L. T., “Critical Distances in Proton Diffraction,” Phys. Letters 24A, 686, (1967).Google Scholar
10. Cowley, J. M., “The Channeling of Fast Charged Particles Through Crystals,” Phys. Letters 26A, 623 (1968).Google Scholar
11.Proc. Brookhaven International Conference on Solid State Physics Besearch with Accelerators, ML 50083, national Bureau of Standards, 1968.Google Scholar
12. Alam, M. N., Blackman, M. and Pashley, D. W., “High Angle Kikuchi Patterns ,” Proc. Roy. Soc. 221, 224 (1954).Google Scholar
13. Kainuma, Y., “Theory of Kikuchi Patterns,” Acta Cryst. 8, 247 (1955).Google Scholar
14. Kainuma, Y. and Kogiso, M., “Many Beam Dynamic Theory of Lines in Middle of a Kikuchi Band,” Acta Cryst. A24, 81 (1968).Google Scholar
15. Cowley, J. M. and Moodie, A. F., “The Scattering of Electrons by Thin Crystals,” J. Phys. Soc. Japan 17, Suppl. B-II, 86 (1962).Google Scholar