Abstract
CuKβ radiation with a wavelength of λ = 1.3923 ? is recommended for crystal structure determination from X-ray powder diffraction using the Rietfeld method. A highly sensitive image plate detector is able to collect enough intensity to record a brilliant X-ray powder pattern in a reasonable time, compared to CuKα1 radiation used today. Especially atomic displacement coefficients could be determined more precisely with the much greater number of reflections recorded. A double-radius Guinier camera attached to a micro-focus rotating anode tube ensures increased brilliance besides high resolution. A simple construction specification is presented to make smart cylindrically bent Ge(111) or Si(111) X-ray monochromators that deliver focused CuKβ radiation. The highly linear response of image plate detectors allows removing of fluorescence radiation simply as background of the pattern. The proposed equipment is a cost-efficient alternative to a liquid gallium-metal-jet X-ray source with maximum power load and a similar wavelength of λ(GaKα1) = 1.34013 ?.
Highlights
CuKβ radiation with a wavelength of λ = 1.3923 Å is recommended for crystal structure determination from X-ray powder diffraction using the Rietfeld method
By application of the Rietfeld method for crystal structure determination on powders using CuKα1 radiation the limiting data set of reflections accessible considerably influenced the reliability of the structure parameters
In order to work with CuKβ radiation for crystal structure determination atomic scattering factors as well as attenuation factors must be available
Summary
By application of the Rietfeld method for crystal structure determination on powders using CuKα1 radiation the limiting data set of reflections accessible considerably influenced the reliability of the structure parameters. The present author recommended a more routine use of CuKβ radiation, in contrast to a more expensive gallium-metal-jet X-ray source [3], on the basis of some improvements, which are reported in this article This improvements cover, besides a well constructed monochromator, a different camera setting of subtractive chromatic dispersion, and a stripe by stripe read out routine of the imaging plate to increase the intensity and open the possibility for texture diagnosis and correction. The publication of this contribution is encouraged by several thousand reads of a pre-published version in Researchgate.net
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