On Wed, 23 Jun 1999, Jacco van de Streek wrote:
> Daniel M. Toebbens wrote:
> >
> > Does anybody know about a good calibration standard which can be
> > used for peak shape control in the low angle region in neutron powder
> > diffraction? Low angle meaning 2Theta = 5� - 20� with a wavelength of
> > 1.6Ang -- a d-range of 20 Ang - 4.5 Ang. In this region the material
> > should have a few a) strong and b) well resolved reflections.
>
> R. Gilles, U. Keiderling and A. Wiedenmann, "Silver behenate powder as a
> possible low-angle calibration standard for small-angle neutron
> scattering", J. Appl. Cryst. 31 (1998), 957-959.
>
Yes, we tried this - after all, Gilles works at our institut :-) But
silver behenate has a c lattice parameter of 58 Ang. With our wavelength
of 1.6 Ang the (001),(002),(003) reflections are at angles below 5� where
we have problems to record them. And higher order (00l) reflections are
weak. Silver behenate should be a good standard for real small-angle
scattering, but it is "too good" for our purpose ;-)
Daniel Toebbens
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Daniel M. Toebbens Tel.: +49 30 8062-2793
Hahn-Meitner-Institut Fax : +49 30 8062-2999
Glienicker Strasse 100
D-14109 Berlin, Deutschland http://www.hmi.de/people/toebbens/
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