Dear Frank,
Small-molecule fcf files are usually created (by SHELXL) using the LIST
4 instruction and do not contain the phase information needed to make a
map. To read the fcf into Coot you need LIST 6 format. You can check
this by looking at _shelx_refln_list_code near the start of the fcf
file. Assuming that you have a LIST 4 fcf file,
you need to run PLATON (as pointed out by John) to make the SHELXL .ins
and .hkl files and then run SHELXL with the LIST 6 command inserted in
the ins file, then you can input the resulting res and fcf files into
Coot. Even better, you can ask whoever gave you the files for their ins
and hkl files (they must have refined the structure with SHELXL because
as far as I know, only SHELXL writes fcf files).
However in my experience Coot may not display the bonds correctly for a
typical small molecule without a known residue name. There are several
excellent small molecule GUIs that are much more suitable for displaying
small molecules and their maps. We use sheXle which is particularly
simple and intuitive but Olex2 is also popular. These two are free, in
the case of shelXle also for commercial users. They also support various
stereo modes. You can google them to get the downloading information.
Best wishes, George
On 05/09/2012 10:22 AM, John R Helliwell wrote:
> Dear Frank,
> PLATON.
> [Or make the transition to bond distances and angles with esds,
> instead of maps.]
> Greetings,
> John
>
> On Wed, May 9, 2012 at 6:10 AM, Frank von Delft
> <[log in to unmask]> wrote:
>> Hi daft question: I was sent cif and fcf files for a small molecule crystal
>> structure - solved with Bruker software, I think.
>>
>> Anybody know how to display this as electron density maps? I tried coot and
>> mg, they barfed though - not sure whether that's a file problem though.
>>
>> Thanks for help!
>> phx
>
>
--
Prof. George M. Sheldrick FRS
Dept. Structural Chemistry,
University of Goettingen,
Tammannstr. 4,
D37077 Goettingen, Germany
Tel. +49-551-39-3021 or -3068
Fax. +49-551-39-22582
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