Hi Deng, On Tue, 2011-04-05 at 07:31 +0200, Poul Nissen wrote: > Deng, > You need a good synchrotron source with a low point spread detector, > but not least a careful consideration in crystal mounting so that your > crystal rotates apprx around the long axis during data collection to > optimise the separation of reflections on the detector
If you go to a beamline that has a goniostat with a kappa axis you will be able to orient the long axis of your crystal after mounting to minimise overlaps. You don't say where you are located, but there are quite a number of beamlines that are suitable for this kind of work in Europe. I am not so familiar with the instrumentation available at MX beamlines in the USA, but I believe that there are possibilities there as well. Regards, Peter. > ....besides checking that the long axis is not a result of bad cryo > and crystal deterioration during flash cooling > Poul > > > > > On 05/04/2011, at 07.05, dengzq1987 <dengzq1...@gmail.com> wrote: > > > > > hello all, > > does anyone have the experience of > > Collecting Data from Long Unit Cell Axes ? I have a crystal that > > diffracts to about 4 A. in some direction the spots overlap. we > > can't use the data to index .we think it is because that there is a > > long unit cell axes. so is there any method to solve this problem? > > > > best wishes. > > > > 2011-04-05 > > > > ____________________________________________________________________ > > dengzq1987 -- Peter Keller Tel.: +44 (0)1223 353033 Global Phasing Ltd., Fax.: +44 (0)1223 366889 Sheraton House, Castle Park, Cambridge CB3 0AX United Kingdom
