Hi Peter,

thanks. 

here the Rvalues after rigid body refmac:

                  R          Rfr   
P6122      0.371    0.377
P61          0.361    0.369
P31          0.337    0.338  twin
P3121      0.376    0.378  twin
P321        no solution


Now, RvsR stats in P3121 are as following:

R_abs_twin observed data   : 0.155
R_abs_twin calculated data  : 0.372

"Twins with RPS" (Lebedev, Vagin, Murshudov 2006, Acta Cryst. D62,83-95).

But the refinement doesnt look better than P31.

Thanks again. Cheers,

Gabriela
 

On Sat, Jan 2, 2010 at 5:45 PM, Peter Zwart <phzwart@gmail.com> wrote:
Hi Gabriela,

Can you give us some more info? What are the excat r-values in all space groups?

How does the refinement in p321 or p312 look?

Cheers,

Peter


2010/1/2 Gabriela Guédez <gguedez@gmail.com>:
> Hi Phenixbb,
>
> I have a data that indexes in P6122, also P61 and P31. Data analysis in
> phenix.xtriage says no twinning is suspected according to the L-test.
>
> However, after MR and twin RB refinement, the model improves from P6122 or
> P61 to P31 5% Rfacs and 0.5 the FOM.
>
> I thought the data might have RPS and twinning not detected with the L-test.
> So, i ran xtriage to compute the RvsR statistics using the obs_and_calc.mtz
> file and the results were:
>
>
> in P61
> R_abs_twin observed data   : 0.112
> R_abs_twin calculated data : 0.047
>
>
> in P31
> R_abs_twin observed data   : 0.117
> R_abs_twin calculated data : 0.139
>
> "misespecified crystal symmetry", according to Lebedev, Vagin, Murshudov et
> al 2006, Acta Cryst. D62,83-95.
>
> I would like to know a test that tells me the right symmetry.
>
> I appreciate your help. Thanks,
>
> Gabriela
>
> _______________________________________________
> phenixbb mailing list
> phenixbb@phenix-online.org
> http://phenix-online.org/mailman/listinfo/phenixbb
>
>



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P.H. Zwart
Beamline Scientist
Berkeley Center for Structural Biology
Lawrence Berkeley National Laboratories
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Gabriela Guédez R.
gabriela.guedez@bzh.uni-heidelberg.de