At 20:53 11/11/2006, Vincent Favre-Nicolin wrote:
>I'm finishing adding CIF import to FOX. Crystal structure works fine and 
>I've just begun looking at the powder data part and it seems that some powder 
>data cifs from Acta Cryst C have wrong weights. See:

At 00:44 14/11/2006, Vincent Favre-Nicolin wrote:
>   Hmm, caught another few errors in powder data from:
>http://scripts.iucr.org/cgi-bin/sendsup?cnor=fa1185&type=powderdata
>   Some lines which are obviously comments but not beginning with #, and in 
>the two files the second pattern (2nd bank) misses the head "loop_".

I forwarded these questions about IUCr powder CIF's to Mike Hoyland. He tells 
me that the first 3 files mentioned are apparently non-typical, and the weights 
given are more to do with author error in constructing the CIF than with IUCr 
CIF checking, which is routinely done. The errors in the format of the last 
IUCr file mentioned are being corrected. pdCIFplot that Brian mentioned seems 
to be a good method for picking up errors that Encifer cannot find. 

BTW, Juan confirms that FullProf will output CIF files if parameter RPA=-1 (see 
setup text file fp2k.inf) but of course the format of these should still be 
checked with Encifer, pdCIFplot etc...

Finally Jmol as implemented in ICSD is a good application for drawing 
structures from CIFs, and measuring bond lengths and angles etc. Drawing the 
structure is also a good method for checking for obvious errors in the actual 
CIF co-ordinates, symmetry operations etc. that simple format checking will not 
find.

Alan.

_____________________________________________________________
Dr Alan Hewat, ILL Grenoble, FRANCE<[EMAIL PROTECTED]>fax+33.476.20.76.48
+33.476.20.72.13 (.26 Mme Guillermet)  http://www.ill.fr/dif/people/hewat/
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