Subject: N-H..N(S) H-BONDS AND SEMI EMPIRICAL MO

From: "Marais, Charles F. " <[email-masked]>
Date: Fri, 21 Jan 1994 10:36:21 SAST-2

Hi All

I would appreciate some info and references on the suitability of 
AM1, PM3, Zindo and other semi-empirical methods for the 
calculation of H-bond energies and vibrational frequencies for 
N-H..N and N-H..S  hydrogen bonds.

We have a molecule which switches from one to the other, giving 
rise to two clearly separate N-H stretching frequencies.  What we 
want is to calculate positions for the hydrogens which reproduce 
the difference between the stretching frequencies, and possibly 
the position of the bands as well.
How feasible is this ?

Thanks in advance

Charles

Dr Charles Marais

Department of Chemistry
University of Cape Town
Private Bag
Rondebosch                                  [email-masked]
South Africa 7700                           [email-masked]
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