Hi Greg, There are many different distance and angle criteria depending on the different donor and acceptor atom types. These cutoffs are in tables 5-8 of the reference cited in the page you were viewing: Three-dimensional hydrogen-bond geometry and probability information from a crystal survey. Mills JE, Dean PM. J Comput Aided Mol Des. 1996 Dec;10(6):607-22. <http://www.ncbi.nlm.nih.gov/pubmed/9007693> <http://www.springerlink.com/content/m34t237u46784242/> I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco On Dec 14, 2009, at 4:32 PM, Greg Friedland wrote:
Also, I'm curious what cutoffs are used. I looked at http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/findhbond/findhbond... but I was hoping for more details. I.e what numbers from the paper are used for the proton-acceptor distances, donor-proton-acceptor angle and the corresponding dihedral angle.