Dear All,
re identifying metals,
It's possible to calculate crystallographic element-specific anomalous difference maps if you can collect data on either side of the absorption edge. I have used this successfully for Sr, Zn and Mn.
http://www.ncbi.nlm.nih.gov/pubmed/15858259
I have a set of scripts to conveniently calculate such a map, which I can send off list.
James
--
Dr. James W. Murray
David Phillips Research Fellow
Division of Molecular Biosciences
Imperial College, LONDON
Tel: +44 (0)20 759 48895
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From: CCP4 bulletin board [[log in to unmask]] on behalf of Frank Murphy [[log in to unmask]]
Sent: Wednesday, July 25, 2012 3:03 AM
To: [log in to unmask]
Subject: Re: [ccp4bb] How to identify unknow heavy atom??
Dear Haytham,
It should be relatively simple (and quick) to determine the metal in your sample employing either crystallized sample or solution using X-ray fluorescence (http://en.wikipedia.org/wiki/X-ray_fluorescence) at any beamline with a silicon drift detector (http://www.amptek.com/drift.html) set up for energy dispersive spectrometry (EDS).
We perform these analyses regularly at NE-CAT and I am sure there are a number of other beamlines set up for the experiment.
Frank Murphy
Beamline Scientist
NE-CAT / Cornell University
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