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Date: Tue, 29 Dec 1998 15:08:22 -0400 (AST)
From: "J. Sichel" <sichelj@Umoncton.ca>
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To: "E. Lewars" <elewars@alchemy.chem.utoronto.ca>
cc: chemistry@www.ccl.net
Subject: Re: CCL:RATE CONSTANT AND BARRIER-QUESTION
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On Mon, 28 Dec 1998, E. Lewars wrote:

> True or false:
> 
> Two reactions with exactly the same free energies of activation (delta G
> of activation, not Arrhenius activation energy) _must_ have the same
> rate constants (at the same temperature). 

I can think of two reasons why not.
1. The transition-state-theory expression for k includes a barrier
   transmission coefficent (denoted by kappa) which may vary between
   reactions.
2. Transition-state theory may not be exact for the reactions in question.

     John-M. Sichel
     Dept. de chimie et biochimie
     Universite de Moncton
     Moncton NB, Canada