Subject: Re: CCL:Pseudorotation?

From: "C.F. Matta" <[email-masked]>
Date: Mon, 17 Jan 2000 23:50:10 -0500 (EST)

Dear Dr. Harris,
 You may try:
[1] D.Cremer & J.A.Pople "A general definition of rung puckering
    coordinates" J.Am.Chem.Soc 97 (1975) 1354-1358.
[2] D.Cremer & J.A.Pople "Molecular orbital theory of the electronic
    structure of organic compounds. XXIII. Pseudorotation in saturated
    five-membered ring compounds.  J.Am.Chem.Soc 97 (1975) 1358-1367.
    (and references theirein). 
Take care
	  C.F.Matta
.......................................................................
 Cherif F. Matta		  	tel. (905) 525-9140 ext. 22502
 Chemistry Department                   fax  (905) 522-2509
 McMaster University                      
 Hamilton, Ontario, CANADA L8S 4M1.
.......................................................................

On Mon, 17 Jan 2000, Robert E. Harris wrote:

> Can anyone refer me to papers discussing the small barrier motions in small
> ring systems that Bill Gwinn and coworkers described as "pseudorotation"
> about 35 years ago?  What I am looking for is methods of calculating
> contributions to thermodynamic properties (energy, entropy) from such
> motions.
> REH
> 
> Robert E. Harris  Phone: 573-882-3274  Fax:  573-882-2754
> Department of Chemistry, University of Missouri-Columbia
> Columbia, Missouri, USA 65211
> 
> 
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---

From: Jochen Kuepper <[email-masked]>
Date: Tue, 18 Jan 2000 11:09:37 +0100

>ring systems that Bill Gwinn and coworkers described as "pseudorotation"

What exactly do you mean by pseudo-rotation.
Pseudorotation like Na_3 pseudo-rotation, or ringpuckering (e.g.
5-membered rings), or ...  ?

Anyway, Jon Hougen comes to mind,also Laane. For ringpuckering look for
Laane's publications, the last I saw where on 1,3-Benzodioxole - 
JACS 121(1999), 5056

>contributions to thermodynamic properties (energy, entropy) from such

Good luck :-)

-- Jochen
        Heinrich-Heine-Universität, Institut für Physikalische Chemie I
        Universitätsstr. 1, Geb. 26.43.02.29, 40225 Düsseldorf, Germany
phone 02118113681 fax 02118115195  --  www-public.rz.uni-duesseldorf.de/~jochen
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