Hi,

I used the automated H-bond detection of Chimera to detect H-bonds between an target protein and its docked lignds.
On your webpages (http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/findhbond/findhbond.html) I found the following:

"[...] Relax H-bond constraints indicates that tolerances to Relax constraints by should be applied to the precise geometric criteria [...]; empirically, tolerances of 0.4 angstroms and 20.0 degrees work well for most macromolecular structures."  

Can you lease tell me if there is a literature which discusses this relaxation in more detail and can be referenced
Many thanks for a reply.

Cheers
Joern