[ccp4bb]: unknown cation at 2.6-3.0A bonding distances

["Aleks Roszak" <aleks@chem.gla.ac.uk>]

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Dear all,

Could you please suggest any good site, database or so, in which I could find
details of coordination (bond distances, coordination geometry, etc) for some
light metal ions, or even better any single atom ions.

I seem to have an ion [quite spherical density up to 6sigma, definitely much
higher than water, refines to B=2.0 while average B for this structure is 26
(from TLS refinement)] coordinated by 3 main-chain carbonyl oxygens of a loop,
and possibly also by 2 water molecules, at distances of 2.6-3.0A. The three
carbonyl oxygens plus one water molecule oxygen form approx. a (relatively
flat)
pyramid with the unknown ion at the apex.

Any suggestions are appreciated, thanks.

Aleks

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* Aleksander W. Roszak, Ph.D.               E-mail: aleks@chem.gla.ac.uk *
* Protein Crystallography                   Fax:     +44-(0)141-330 4888 *
* Department of Chemistry                   Tel:     +44-(0)141-330 4476 *
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