Dear Mark, It does happen, even that two crystals from the same drop (everything identical) have different space groups.
Best, Herman -----Ursprüngliche Nachricht----- Von: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] Im Auftrag von Markus Heckmann Gesendet: Donnerstag, 9. November 2017 11:02 An: CCP4BB@JISCMAIL.AC.UK Betreff: [EXTERNAL] [ccp4bb] double cell dimensions between P2 and C2 Dear all, From a small protein, gives crystals P2 with cell Cell 53.16 65.73 72.89 90 110.94 90 (has 3 molecules in the asymmetric unit). Tested with pointless. Does not give any other possibility. Another crystal if the same protein, similar conditions: C2 Cell 109.14 124.37 73.42 90 111.75 90. This has 6 molecules in the a.s.u. Tested with pointless. Does not give any other possibility. The cell length a, b of C2 is twice that of P2. Is it usual to get such crystals from similar conditions or am I missing something? Many thanks, Mark
