Synchrotron is useless if :
- The problem is too simple : less than 500 reflections on the powder pattern. The Cubic (Im3, a = 18Å) fullerene powder pattern shows absolutely no gain with the synchrotron 10 times best resolution data : no less overlapping, because the strictly overlapping reflections continue to overlap exactly, of course.
- The sample is really ill crystallized : the bismuth sub-salicylate structure will be hard to solve with the synchrotron data as well as with the conventional X-ray data. Using synchrotron for nanocrystalline compounds will not be very informative.
- The short wavelenght selected (l
£ 0.8 Å)
combined with a medium synchrotron resolution (FWHM ³
0.05° 2q ) do
not really beat the conventional X-ray performances (case of the tetracycline
Use synchrotron when it makes
a BIG difference
And remember that crystals as small as 20x20x20m (or even smaller) in your "powder" are large enough for a single crystal study (was the case of the SDPDRR sample II).