Hostname: page-component-745bb68f8f-b95js Total loading time: 0 Render date: 2025-02-10T05:41:39.575Z Has data issue: false hasContentIssue false
  • English
  • Français

A Versatile Bragg-Brentano/Seeman-Bohlin Powder Diffractometer

Published online by Cambridge University Press:  06 March 2019

H.W. King ,
C.J. Gillham  and
F.G. Huggins
H.W. King
Affiliation:
Imperial College London, S.W.7, England
C.J. Gillham
Affiliation:
Imperial College London, S.W.7, England
F.G. Huggins
Affiliation:
Imperial College London, S.W.7, England
Get access

Abstract

An interchangeable Bragg-Brentano:Seeman-Bohlin diffractometer, with variable specimen setting, has been constructed. A study of the influence of the geometry on the resolution, angular displacement and intensity of diffraction profiles clearly demonstrates that the standard Bragg-Brentano method is to be preferred when recording Bragg reflections below 40°,2θ. At higher Bragg angles, which permit the specimen to be set further away from the X-ray source, it is demonstrated that the diffracted intensity of the Seeman-Bohlin method can be increased above that of the Bragg- Brentano because the use of an increased divergent angle does not reduce the resolution. A study of the effect of specimen setting on the systematic errors associated with the Seeman- Bohlin geometry indicates that a setting of 60° (half-angle from the X-ray source) gives optimum resolution with minimum displacement error.

Type
Research Article
Information
Advances in X-Ray Analysis , Volume 13: Eighteenth Annual Conference on Applications of X-ray Analysis, August 6-8, 1969 , 1969 , pp. 550 - 597
Copyright
Copyright © International Centre for Diffraction Data 1969

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. Klug, H. P. and Alexander, L. E., “X-ray Diffraction Procedures”, John Wiley and Sons., Inc., New York, 1954.Google Scholar
2. Vassamillet, L. F. and King, H. W., “Diffractometer Techniques”, in the Handbook of X-rays, Ed. Kaelble, , McGraw-Hill Book, Co., Ltd., New York, 1967.Google Scholar
3. Parrish, W. and Mack, M., “Seeman-Bohlin X-ray Diffractometry, I Instrumentation; II Comparison of Aberrations and Intensity with Conventional Diffractometer”, Acta Cryst. 23, 687–693, 1967.Google Scholar
4. Das Gupta, K., Schnopper, H. W., Metzer, A. E. and Shields, A. R., “A Combined Focusing X-ray Diffractometer and Non-dispersive X-ray Spectrometer for Lunar and Planetary Analysis”, Advances in X-ray Analysis, Plenum Press, 9, 221, 1966.Google Scholar
5. Pike, E. R., “Focusing Geometry in X-ray Diffractometer”, J. Sci. Instrum. 39, 222, 1962.Google Scholar
6. Baun, W. L. and Renton, J. J., “The Design and Use of Special- Purpose Attachments for the Horizontal Diffractometer”, Advances in X-ray Analysis, Plenum Press, New York, 7, 302, 1964.Google Scholar
7. Wassermann, G. and Wiewiorosky, J., “Uber ein Geiger-Zahlrohr- Goniometer nach dem Seeman-Bohlin Prinzip”, Z. Metallk. 44, 567, 1953.Google Scholar
8. Vassamillet, L. F. and King, H. W., “Precision X-ray Diffractometry using Powder Specimens”, Adv. in X-ray Analysis, Plenum Press, New York, 6, 142, 1963.Google Scholar
9. Parrish, W. and Wilson, A. J. C., International Tables for X-ray Crystallography, Vol. 11, 216, 1959, Kynoch Press, Birmingham, England.Google Scholar
10. Segmuller, A., “Die Bestimmung von Glanzwinkeln, Linienbreiten und Intensitaten der Rontgen-Interferenzen mit einem Geiger- Zahlrohr-Goniometer nach dem Seemann-Bohlin-Prinzip”, Z. Metallk. 48, 448, 1957.Google Scholar
11. Kunze, G., “Korrekturen hoberar Ordnung fur die mit Bragg- Brentano und Seemann-Bohlin-Systernen gewonnenen Messgrossen etc.,” Z. Angew. Phys. 17, 412, and “Intensitats-, Absorptions- und Verscbiebungsfaktoren von Interferenzlinien bei Bragg- Brentano- und Seemann-Bohlin-Diffraktometern I and II”, Z. Angew. Phys. 17, 522 and 18, 28, 1964.Google Scholar
12. Wilson, A. J. C., “Correction of Lattice Spacings for Refraction”, Proc. Camb. Phil. Soc., 36, 485, 1960.Google Scholar
13. Wilson, A. J. C., “Effect of Absorption on Mean Wave-Length of X-ray Emission Lines”, Proc. Phys. Soc., (London), 72, 924, 1958.Google Scholar
14. Cermak, J., “The Intensity Distribution in the Faces of Curved Crystal Monochromators and an Estimate of Its Influence on Precision Measurements of Lattice Parameters”, Acta Cryst. 13, 832, 1960.Google Scholar
15. Lonsdale, K., International Tables for X-ray Crystallography, Vol. 111, 1962, Kynoch Press, Birmingham, England.Google Scholar
16. Beardon, K., “X-ray Wavelengths”, U.S. Atomic Energy Commission, Division of Technical Information Extension, Oak Ridge, Tenn., 1964.Google Scholar
17. Pike, E. R., “Counter Diffractometer - The Effect of Dispersion, Lorentz and Polarization Factors on the Position of X-ray Powder Diffraction Lines”, Acta Cryst. 12, 87, 1959.Google Scholar
18. Gillham, C. J. and King, H. W., “Seeman Bohlin Diffractometer - Effect of Dispersion, Lorentz factor and Polarization on the Position of Diffraction Profiles”, to be published.Google Scholar
19. Pike, E. R., “Counter Diffractometer - The Effect of Vertical Divergence on the Displacement and Breadth of Powder Diffraction Lines”, J. Sci. Instrum. 34, 355, 1957.Google Scholar
20. Evans, J. C. and Taylerson, C. O., “Measurement of Angle in Engineering”, Nat. Phys. Lab. Notes on Appl. Sci. No. 26, 1961, H.M. Stationery Office, London.Google Scholar
21. King, H. W. and Vassamillet, L. F., “Precision Lattice Parameter Determination by Double-Scanning Diffractometry”, Advances in X-ray Analysis, Plenum Press, New York, 5, 78, 1962.Google Scholar
22. Wilson, A. J. C., “Geiger-Counter X-ray Spectrometer - Influence of Size and Absorption Coefficient of Specimen on Position and Shape of Powder Diffraction Maxima”, J. Sci. Instrum., 27, 321, 1950.Google Scholar
23. Parrish, W., “Results of the I.U.Cr. Precision Lattice Parameter Project”, Acta Cryst. 13, 838, 1960.Google Scholar
24. Delf, B. W., “The Practical Determination of Lattice Parameters using the Centroid Method”, Brit. J. Appl. Phys. 14, 345, 1963.Google Scholar
25. Parrish, W., Taylor, J. and Mack, M., “Dependence of Lattice Parameters on Various Angular Measurements of Diffraction Line Profiles”, Advances in X-ray Analysis, Plenum Press, New York, 7, 66, 1964.Google Scholar
26. King, H. U. and Russell, C. M., “Double-Scanning Diffractometry in the Back-Reflection Region”, Advances in X-ray Analysis, Plenum Press, New York, 8, 1, 1965.Google Scholar
27. Franks, A., “The Precision Measurement of Lattice Parameters using a Back Reflection Focusing Camera”, N.P.L. Report No., M.3072, 1963.Google Scholar