I agree. Large crystals often diffract more poorly than smaller ones. I would hazard a guess that large crystals may experience more mechanical distortion during flash cooling, but it's just a guess. In our lab, the sweet spot for most of our crystals is 0.3-0.4 mm. Larger is usually worse, and smaller has weaker scattering.
Cheers, Roger Rowlett On 4/14/10, W H <[email protected]> wrote: > 50% solvent content in a small crystal is still 50% solvent content in > a large crystal given the same crystal form, so it's tough to use that > to explain loss of diffraction. > > Very large crystals in my hands seem to suffer from more problems of > mechanical stress. > > > > William > > > On Wed, Apr 14, 2010 at 5:36 PM, syed ibrahim <[email protected]> > wrote: >> Hi All >> >> I had two crystals grown in same well, one is small and other is 10 times >> bigger. I treated both crystal in same cryo and same time. The smaller one >> diffracted to 2.5A and the bigger one to 6-7A. I was expecting the bigger >> one to diffract high resolution. >> >> I assume the bigger crystal might have lot of solvent which prevent for >> high resolution. If it is true what could be the best way to dehydrate >> crystal without affecting crystal quality? >> >> Thank you >> >> Syed >> >> PS: Taken care of less solvent to be present in the loop >> >> >> >> > -- Sent from my mobile device
