Pharmaceutical XRD Data plus warning for International Quant Analysis Round Robin participants

Lachlan Cranswick l.cranswick at dl.ac.uk
Mon Jan 26 21:23:41 EST 1998



Hi All,

Announcement relating to the International Union of Crystallography, 
Commission on Powder Diffraction, Quantitative Analysis Round Robin.

If other people in your department or laboratory may be interested in
this International Quantitative Analysis Project, please consider 
posting up a printout of the web-page the local notice-boards - 
or forwarding this message on.

Topics for today's message:
 - Warning about Siemens/Bruker and XDA formatted data grabbed 
   from CPD Round Robin Web site prior to Jan 26 1998.
 - Pharmaceutical Powder XRD Data now Available for Analysis.

-----

Warning: about converted data on the CPD Quantitative
Analysis Round Robin Web Site at:
   http://www.dl.ac.uk/SRS/XRD/IUCR/QARR/
   http://www.dl.ac.uk/SRS/XRD/IUCR/QARR/data-kit.htm
Up till Jan 26, Bruker/Siemens RAW files and XDA format files
were not converted correctly.  If anyone grabbed these files
previous - clear the cache of your web-browser, press the
reload button and grab these files again.  
If unsure or you wish to check validity of converted files - 
compare with the LHPM *.dat files on the web site.  
Be aware that due to the different ways programs interpret 
the compress/encrypted Philips RD XRD format for reading 
and conversion - counts may be not completely identical -
but very close within an ESD of the "X-ray count".  
The Philips RD format is known for using a compression/
encryption method that slightly modifies the raw counts 
passed from the XRD to the Philips datalogging software RD 
files.  Best place for more elaboration on this is the VLGM 
list where this has been a known and discussed problem:
  http://www.geol.uni-erlangen.de/vlgm/index.html
(No room here for a big rant on binary raw data formats - 
"It's not malicious - just incrediably evil!")

-----

Pharmaceutical Powder XRD Data now Available for Analysis.

Another update that the "Standard" Pharmaceutical data for the
International Union of Crystallography (IUCr) - Commission on Powder
Diffraction (CPD) - Quantitative Phase Analysis Round Robin is
now available over the web at:
   http://www.dl.ac.uk/SRS/XRD/IUCR/QARR/
   http://www.dl.ac.uk/SRS/XRD/IUCR/QARR/data-kit.htm
(the Inorganic/Mineral samples of course are still there)

Crystal structure information from the literature relevant to
the Pharmaceutical data will be added later on the Web-site. 
This is intended for those who do not have access to 
their own or a library structure database and are using
structure based methods.

---

People who ordered pharmaceutical samples - these are now
in the post.  Please note that people who want to run samples
are not limited to Powder Diffraction in their analytical methods.
(i.e., XRF, Web Chemical, IR, etc can be used) but we request
as their is no chemical ambiguity in the phases/compounds present
(as was originally intended) that you use your "usual" single
method - whatever that may be.

---

Other updates are:

Besides the standard data archived in ZIP format, 
tar.Z and tar.gz have now been added.  
Other data formats are slowly being added - latest is DBWS format.
Nearly every Powder Diffraction program in existence should be
able to use one of the formats present - with possible minor
changes in the header(?).  If not, please email me.

It has been reported that when grabbing individual files, Netscape
seems to be corrupting the binary Siemens/Bruker RAW and Philips
RD files (might be interpreting them as ASCII?).  Quickish solution
is just to grab one of the archive files.

----

Again, if any queries on this, feel free to email.

Lachlan.



Lachlan M. D. Cranswick
CCP14 for Single Crystal and Powder Diffraction
Daresbury Laboratory, Warrington, WA4 4AD U.K
Tel: +44-1925-603703  Fax: +44-1925-603173  Room C14
E-mail: l.cranswick at dl.ac.uk

Personal Crystallographic WWW:
                    http://www.unige.ch/crystal/stxnews/stx/volnteer.htm
Commission on Powder Diffraction, Quantitative Phase Analysis Round Robin: 
                                  http://www.dl.ac.uk/SRS/XRD/IUCR/QARR/
Society of Crystallogaphers in Australia (SCA):   http://www.sca.asn.au/
Australasian Web Publishers Association: (AWPA):  http://www.awpa.asn.au/
Australian X-ray Analytical Association (AXAA): 
                                  http://www.latrobe.edu.au/www/axaa/





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