From: FX Coudert (fxcoudert_at_gmail.com)
Date: Tue Sep 26 2006 - 14:38:39 CDT

Hi again,

> "Given an atom D with a hydrogen H bonded to it and an atom
> A not bonded to atom D"
>
> The angle criterion is indeed D-H-A -- this is the relevant angle for
> hbond energies as well, as you're testing for collinearity of the
> donor,
> hydrogen, and acceptor in that order. In your case, the D-H-A angle is
> 42.39 degrees

It looks like I finally understood: when you mean "angle D-H-A", you
mean "angle between the DH and HA vectors, while I mean \hat{DHA},
the angle between vectors HD and HA. Could the documentation be
updated to reflect that fact? Also, I'd be happy to have (and it
might be a worthy addition to the documentation) a reference for that
geometric criterion.

And also, last but not least, would implementation of other criteria
be acceptable?

FX