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The effect of particles on the absorption factor for diffracted X-rays in single-phase powders measured at cylindrical geometry— a computational study

Published online by Cambridge University Press:  10 January 2013

J. Collazo
Affiliation:
Institute of Solid State and Materials Research Dresden, Postfach 270016, D-01171 Dresden, Germany
H. Hermann
Affiliation:
Institute of Solid State and Materials Research Dresden, Postfach 270016, D-01171 Dresden, Germany
A. Teresiak
Affiliation:
Institute of Solid State and Materials Research Dresden, Postfach 270016, D-01171 Dresden, Germany
K. Wetzig
Affiliation:
Institute of Solid State and Materials Research Dresden, Postfach 270016, D-01171 Dresden, Germany

Abstract

The results of computer simulations of the absorption of diffracted X-rays in single-phase powders measured at cylindrical (or Debye–Scherrer capillary) geometry taking into consideration the size of the powder particles are presented. The samples are simulated by random dense packings of equal spheres. The calculations are carried out for different values of the ratio, Da, of particle size to cylinder diameter, the product, κ, of linear absorption coefficient and cylinder radius and the scattering angle 2θ. Strong deviations of the absorption factor from the values for the ideal case of very fine particles are found in the region 0≤2θ≤30°, and for medium and high values of κ,(κ≥5) and Da (Da≥0.002). The consequences for the experiment are discussed.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1998

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