A more recent survey could possibly be of help to you

Yes, I'd been looking at Zheng et al's 2008 paper reporting the NEIGHBORHOOD database, and the Fe-ligand distances that I observe in my structure are significantly outside of this range (by up to ~35%). I'm going to further into this and maybe pose the question to a broader audience at some point.

but you have data that may be telling you what you need to do. You can also add a slack option to the edit which makes the potential well flat bottomed. If you made it say 0.2 then the metal coordinate would be very flexible and you wouldn't have the nonbonded term pushing them apart.

Ah! I hadn't known about the slack parameter; now I know (this is now bookmarked: http://www.phenix-online.org/download/documentation/cci_apps/structure_refinement.html). Thanks to you both!

Emily.

Cheers

Nigel

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Nigel W. Moriarty
Building 64R0246B, Physical Biosciences Division
Lawrence Berkeley National Laboratory
Berkeley, CA 94720-8235
Phone : 510-486-5709 Email : NWMoriarty@LBL.gov
Fax : 510-486-5909 Web : CCI.LBL.gov