Newsgroup sci.techniques.xtallography 3032

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Oxford Cryosystems is holding a once monthly competition to win a copy 
of our software tool kit Crystallographica (value $995).  Visit our 
Competition Page at:
http://www.demon.co.uk/oxcryo/comp.html
Good luck!

Posted on behalf of Christer Svensson (christer.svensson@oorg2.lth.se)
Cheers, Lachlan.
=========================================================
Lund University announces a position as
Professor of Solid State Chemistry
Chair located at the Centre for Chemistry and Chemical Engineering.
Reference number 3497.
The board of the university has not stipulated any further description
of the field concerned in addition to that made apparent by the title 
of the position.
Suitability for the position is to be attested with regard to scientific
competence within the discipline of solid state chemistry. Furthermore,
suitability with regard to pedagogical skill within post-graduate
supervision and teaching and in undergraduate teaching should be proven.
Successful work-place administration and managing of projects also
provide valuable experience. In evaluating suitability for the position,
attention will also be paid to how applicants may, through their skill
and experience, complement the chemical research and strengthen the
chemical engineering research being carried out at the Centre for
Chemistry and Chemical Engineering. The teaching duties of the post
include inorganic chemistry, solid state chemistry and materials
chemistry.
The majority of the professors at the Lund Institute of Technology are
men. The university therefore welcomes female applicants to the post.
Applications in English should comply with instructions obtainable by
email from:  eva.persson@kansli.lth.se.
Applications must reach the desk of the University Registrar,
P.O.Box 117, S-22100 Lund, Sweden, no later than 4 December, 1996.
Further information about
- the Lund Institute of Technology (LTH) and the Dept. of Inorganic
  Chemistry 2:  http://lth.se
- the position: contact the dean, professor Goran Magnusson
  by email at  goran.magnusson@orgk2.lth.se, or
  by phone at intl. + 46-46-222 8215, or
  by fax at intl. + 46-46-222 8209.
- conditions of employment: contact personnel manager Staffan Svensson
  on intl. + 46-46-222 7105 or by fax on + 46-46-222 4610.

I seem to remember that an example was found not too long ago that completed
the representations of all space groups. If this is true I'd be grateful for
the reference since all the ways I know of doing a literature search have
failed. If not, can anyone tell me if there is a space group that has never had
a real example?
In 1992, A.J.C. Wilson, Int. Tables C, p792, maintained that there were no 
reliable organic examples for P2m. There don't seem to have been any added since 
then and the only ones in the Cambridge data base must have been considered by
him. Are there any inorganic examples?
TIA, Jim.
-- 
--                 Dr. James V. Silverton   jvs@helix.nih.gov
                   301-496-1515 (OFFICE)    301-402-3404 (FAX)
    NHLBI/LBC, 10/7N-307, 10 CENTER DR MSC 1676, BETHESDA MD 20892-1676  

I would appreciate some help with a few questions I have about xtallography.
Any references or hints to ref'd journals would especially be nice.  Please
excuse the naivete of my word-usage and questions.
1) What is the most recent problem/dilemma in phase retrieval wrt
xtallography?  
2) When collecting a diffraction/scattering pattern, how much
molecular/protein hinge motion is averaged out (-+10Ang?)?  And how much
degradation or "blurring" does this motion cause in the pattern-image?
3) Is Isomorphic Replacement still the most widely used technique for
acquiring phase information? If not, what is the lastest technique?  If so,
how much distortion/blurring/degradation does the diffused metal ion cause in
the pattern?
4) What species of protein or virii have been crystallized, yet whose
structure has not been solved because of motion? 
5) In enzyme catalysis, how does one acquire a good "frozen" diffraction
pattern of an intermediate or other step during the process/motion of
catalysis?  Is there blurring?
6) Any other thoughts about diffraction pattern degradation/blurring?
Thanks much.
--AC

Hi everyone,
Is someone aware of a compagnie (or Institute or ...) which offer a
service
of x-ray
protein structure determination on a contract base.
Please answer by direct e-mail to scomtois@gel.ulaval.ca.
Thank you,
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Sylvain Comtois
Université Laval, Québec, Québec, Canada
e-mail: scomtois@gel.ulaval.ca
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