Dear Natale
A good quality powder pattern starts with a good quality powder. Using a
2D area detector is probably easier than trying to align a small sample
on a Gandolfi spinner, to increase grain statistics. Also a lower
resolution instrument will have fewer problems for grain averaging. With
a 0.1x0.1x0.1 mm sample volume it can be very difficult to find the
sample again after crushing it, assuming it has not transformed during
crushing.
The following paper has nice examples when the sample was not crushed:
Application of synchrotron through-the-substrate microdiffraction to
crystals in polished thin sections. J. Rius, O. Vallcorba, C. Frontera,
I. Peral, A. Crespi and C. Miravitlles
IUCrJ (2015) 2, 452-463
http://dx.doi.org/10.1107/S2052252515007794
It was done in ALBA at the MSPD beamline.
We have some practice with the 3DXRD technique at the ID11 beamline at
the ESRF, see:
Sørensen, H. O., Schmidt, S., Wright, J. P., Vaughan, G. B. M., Techert,
S., Garman, E. F., Oddershede, J., Davaasambuu, J., Paithankar, K. S.,
Gundlach, C. & Poulsen, H. F. (2012). Z. Kristallogr. 227, 63–78.
http://dx.doi.org/10.1524/zkri.2012.1438
This approach might be useful to characterize your sample, but it is not
the Rietveld method. Another approach would be diffraction tomography
("XRD-CT"), which has a Rietveld based variant:
J. Appl. Cryst. (2011). 44, 1111-1119 [ doi:10.1107/S0021889811024423 ]
Hard X-ray diffraction scanning tomography with sub-micrometre spatial
resolution: application to an annealed [gamma]-U0.85Mo0.15 particle
H. Palancher, R. Tucoulou, P. Bleuet, A. Bonnin, E. Welcomme and P. Cloetens
... or a crystal indexing based variant:
Impurity precipitation in atomized particles evidenced by nano x-ray
diffraction computed tomography , Anne Bonnin, Jonathan P. Wright, Rémi
Tucoulou and Hervé Palancher
Appl. Phys. Lett. 105, 084103 (2014); http://dx.doi.org/10.1063/1.4894009
Obviously I am picking the citations closest to home. Most of these
approaches should be available in most of the x-ray synchrotrons in
Europe. For ESRF the next applications deadline is the 10th September.
Plenty of time to try to measure it on Simon's 4-circle before then :-)
Best,
Jon
On 29/07/2015 14:10, Natale Perchiazzi wrote:
Hola Miguel,
A Gandolfi like setup would be definitely easier. I guess you suggest
alternatevely to crush and dilute the material in a matrix? !
Cheers Natale
Inviato da Yahoo Mail su Android
<https://overview.mail.yahoo.com/mobile/?.src=Android>
------------------------------------------------------------------------
*Da*:"GREGORKIEWITZ MICHAEL" <michael.gregorkiew...@unisi.it>
*Data*:Mer, 29 Lug, 2015 alle 12:16
*Oggetto*:Re: synchrotron beamline info
Dear Natale,
do you think about a Gandolfi like setup? Or can the fragments be
crushed?
best
Miguel
---
michele gregorkiewitz
Dip Scienze Fisiche, della Terra e dell'Ambiente
Università di Siena
via Laterina 8, I-53100 Siena
gre...@unisi.it <javascript:return>, +39'0577'233810
Il 2015-07-29 11:33 Natale Perchiazzi ha scritto:
> Dear All,
> I would need to get good quality powder pattern, suitable for Rietveld
> analysys, working on mineral microcrystalline fragments with
> dimensions around 0.1-0.2 mm. From your experience, which could be an
> European synchrotron beamline with a suitable experimental setup to
> get these data?
> best regards Natale Perchiazzi
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Please do NOT attach files to the whole list <alan.he...@neutronoptics.com>
Send commands to <lists...@ill.fr> eg: HELP as the subject with no body text
The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
