Subject: rotamers in n.m.r. experiment

From: Kay Kreidler <[email-masked]>
Date: Fri, 17 Mar 95 10:14:59 MEZ

Dear netters! 
 
I am investigating conformational equilibria of chemical compounds  
containing Ethane rotors, for example derivatives of succinic acid. I try 
to calculate the amount of each canonical rotamer due to the time axis  
of an n.m.r. experiment in aqueous solution. The programs I use are  
force field programs like MM+ (Hyperchem) and Quanta/CHARMm, semiempirical 
programs like MOPAC93, VAMP 4.4 and the ab-initio program Gaussian92. 
Aside of the question of the reliability of the results of anionic  
structures I am searching for a model substance, in which the rotation is 
slowly enough to show the individual rotamers as *seperate* signals in the 
n.m.r. experiment. Does any one of you remember such a case? 
I will summarize to the mailing list. 
 
Thanks a lot 
 
Kay Kreidler