Re: [ccp4bb] molecule on symmetry axis

2010-10-20 Thread Jacqueline Vitali
Dear colleagues, Thank you for your suggestions. I was able to do the refinement of the sulfates and tartaric acid in phenix by changing the occupancies to 0.33 and 0.5, It appears to me (from the log file and from graphics afterwards) that the program automatically turns off the interaction wit

Re: [ccp4bb] molecule on symmetry axis

2010-10-16 Thread George M. Sheldrick
It is nice to see that another old SHELX feature has now found its way into Phenix-refine: 'PART -N' = 'custom-nonbonded-symmetry-exclusion selection' ?! PART -N is indeed rather useful for the refinement of (solvent) molecules disordered about special positions, for example it allows hydrogens

Re: [ccp4bb] molecule on symmetry axis

2010-10-16 Thread Nicholas K. Sauter
Phenix can refine a tartaric acid on the twofold if you set the occupancy to 0.5 AND set the custom-nonbonded-symmetry-exclusion selection to the tartaric acid. It's a new feature. Nick Sent from my iPhone Nicholas K. Sauter (510)847-1592 cell (510)486-5713 desk On Oct 16, 2010, at 1:25 AM, T

Re: [ccp4bb] molecule on symmetry axis

2010-10-16 Thread Robbie Joosten
ption. Cheers, Robbie Joosten > Date: Sat, 16 Oct 2010 10:25:47 +0200 > From: t...@shelx.uni-ac.gwdg.de > Subject: Re: [ccp4bb] molecule on symmetry axis > To: CCP4BB@JISCMAIL.AC.UK > > Hello Jackie Vitali, > > What happens if you model the tartaric acid as if it were not on

Re: [ccp4bb] molecule on symmetry axis

2010-10-16 Thread Tim Gruene
Hello Jackie Vitali, What happens if you model the tartaric acid as if it were not on a symmetry axis and then let phenix deal with the symmetry? I once had a water of which refmac stubbornly lowered the occupancy to 0.5 even though i kept on bringing it back to 1.0 until I realised that it was on

Re: [ccp4bb] molecule on symmetry axis

2010-10-15 Thread George M. Sheldrick
I try not to advertise SHELX too often on CCP4bb, but this is just the sort of disorder problem that small molecule crystallographers handle successfully and rather frequently with SHELX. The use of 'free variables' for tying occupancies together and restraining distances to be equal is something

[ccp4bb] molecule on symmetry axis

2010-10-15 Thread Jacqueline Vitali
Dear colleagues, I have a tartaric acid on a two fold axis with its two halves related by the two fold. How do I refine this in Phenix? Also I have a SO4 on a 3 fold with S and one O on tthe 3 fold. The other 3 oxygens are related by the 3-fold. How do I refine this in phenix? I can put S and