Dear Faisal,
depending on which program or pipeline you used, may be you overlooked
that there is a native data set and the phases from the derivative used
to extend to the native data set?
If you are sure this is not the case, calculate an anomalous difference
map and take a look. You can use the program anode (part of the shelx
suite), or use the SAD target function of refmac5. If you use refmac5
and 'Auto-open' the output mtz in Coot, Coot automatically creates not
only the direct and the difference map, but also the anomalous
difference map.
Of course the same can be achieved with other refinement programs like
phenix.refine and probably buster, but I would not know the details.
Best,
Tim
On 08/30/2015 05:11 PM, Faisal Tarique wrote:
> Hello everyone
>
> I soaked my crystal with HgCl2 and solved the crystal structure through
> MRSAD phasing. During processing one could see a strong anomalous signal at
> Hg edge, and the structure was solved with a very good electron density and
> refinement statistics. But the problem is that I am not able to locate Hg
> atom in the electron density map. My question is.. If the structure was
> solved using anomalous diffraction from Hg then it should be seen somewhere
> near the structure. Is this a normal phenomenon or there is indeed some
> problem with the map.??
>
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Paul Scherrer Institut
Tim Gruene
OFLC/107
CH-5232 Villigen PSI
phone: +41 (0)56 310 5754
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