Dear Felipe,
you can search for one I per triangle by setting the first parameter of the
MIND command in shelxd to a number like -7. However, I would not recommend
doing this. Even with an anomalous signal up to only 5A, shelxd might be able
to locate the triangle (With e.g. MIND -3.5 2). If in that case, the
substructure contains a triangle with 6A distances, you for sure that your
substructure is correct, and you can more confidently carry out density
modification.
shelxd refines the occupancies of the substructure atoms. This is equivalent
(within experimental error) to searching for different atom types, i.e. shelxd
with automatically search for anomalous scatterers of any kind.
Best regards,
Tim
On Thursday, October 29, 2015 04:52:23 PM Felipe Trajtenberg wrote:
> Dear all
>
> I have a dataset from a crystal soaked with the Magic Triangle (3
> iodides at a distance of 6 Ang) but the anomalous signals goes up to
> 5.5-6 Ang.
>
> Resl. nf. 18.27 11.25 8.47 6.92 5.92 5.21 4.68 4.26 3.92 3.65 3.41
> N(data) 107 314 523 737 937 1154 1371 1614 1845 1971 2336
> Chi-sq 1.77 1.06 0.80 1.02 1.10 1.04 0.98 0.99 1.00 1.09 1.11
> <I/sig> 52.3 57.4 57.1 39.1 29.0 22.2 24.2 23.5 17.7 11.2 6.4
> %Complete 91.5 99.7 100.0 99.6 99.7 99.7 99.4 99.6 99.6 99.3 97.5
> <d"/sig> 5.12 2.78 1.72 1.44 1.36 1.15 1.08 0.94 0.87 0.79 0.81
> CC(1/2) 96.3 85.8 65.7 48.1 42.2 32.7 21.8 13.8 5.1 -3.1 -1.2
>
> is it possible to search for the magic triangle as a superatom?
>
> In addition, the protein has 16 S. How can we look for different types
> of atoms
>
> thanks in advance
>
> Felipe
--
--
Paul Scherrer Institut
Dr. Tim Gruene
- persoenlich -
OFLC/102
CH-5232 Villigen PSI
phone: +41 (0)56 310 5297
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