ISSN:
1600-5724
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
The polarization ratio K is measured for LiF (200) and graphite (00.2) monochromators at different X-ray wavelengths. In each case the kinematical value cos2 2θM is a poor approximation, and the actual value of K may exceed the dynamical limit cos 2θM. An explanation is offered in terms of a model that includes secondary extinction. The effects of an incorrect value of K are studied by refining the model for a ruby standard crystal. The positional parameters are not affected, but the scale, extinction and thermal parameters change. The effects are, however, smaller than the ones observed in the structural parameters due to termination of the data set at lower sin θ/λ values.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0108767386099567
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