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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
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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

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