Pre-screening on standard beamlines

 

 

It is possible to pre-screen crystals mounted on I23 sample holders on the beamline I03. We recommend this procedure for crystals that show a high variability in diffraction quality. Since the screening time is much faster on I03 than on I23, it is a more efficient way to select the best crystals for anomalous data collection on I23.

 

• Users should contact I23 staff to require I23 customed made sample holders (with an estimation of loop number and sizes needed), adapters, combipucks and puck canes.
• As part of their allocated beamtime, users should specifically ask for pre-screening time on I03. Once the visit set up, the dewar can be shipped to I03.
• Once the pre-screening is done, users should rank their best diffracting crystals and communicate the list to the I23 staff who will transfer the samples to I23. Images should be evaluated visually with keeping in mind that ice rings or salt could affect the resolution assessment.

 

To be able to compare the crystals diffraction quality for pre-screening, we recommend using the same data collection settings during the i03 beamtime. See below an example of screening settings. The exposure time might vary with your crystal system. Since the I23 beam typically operates with unfocussed X-ray beam, please select the largest beam on I03 (80x20 um).

 

 

If you have any question, please contact the I23/I03 staff or consult the beamline manuals.

https://www.diamond.ac.uk/Instruments/Mx/I23/I23-Manual.html

https://www.diamond.ac.uk/Instruments/Mx/I03/I03-Manual.html