Subject: Formula accounting for the catalyst effect on entropy.

From: "Park, Tae-Yun" <[email-masked]>
Date: Wed, 28 Aug 1996 16:34:31 +0200 (DFT)

Dear all,

Please let me have your idea on the following problem.

Consider the following reaction,

        +                                  +
      C-C-C  +  C=C-C  --->(TS)--->  C-C-C-C-C     (1) 
                                       C

and focus on the entropy differences between reactants and the transition
state(TS) at 298.15K , i.e.,

                             +
      delta_S* = S(TS) - S(C-C-C) - S(C=C-C)       (2)

If reaction (1) occurs in a catalytic reaction sysem, there should be 
another factor(s) that influences the value of delta_S*.

Under the condition that the entropy values for all the reactants and the
product in *GAS-PHASE* are available, but NOT for the transition state,
my question is,

	is it possible to construct a general formula which includes
        the factor(s) which can account for the catalyst effect?

More clearly, is it possible to relate the delta_S* for catalytic
reaction to gas-phase values of entropies for reactants and product,
and some unknown parameter? I.e.,

  delta_S* = function of 
             [ S(reactants), S(product), parameter] 

If so, what does this equation look like?  Should it be in a kind of
added form, i.e.,

              S(reac) +/- S(prod) +/- parameter(s)
  
or multiplied form, i.e.,

              parameter*S(reac) +/- parameter*S(prod) +/- ...

or something else??

Any suggestion/information(books, articles..)/advice will be
a great help for me.

				Sincerely,

				     Park, TAE-YUN    
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State University of Ghent
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