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Date: Thu, 27 Mar 2003 13:38:51 +0100
From: sergiusz.kwasniewski@luc.ac.be
To: CCL <chemistry@ccl.net>
Subject: question on resonance structures
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Hi,

As you know, poly-acetylene has a doubly degenerate ground state structure, 
because of the Peierls distortion. The skelet structures can be seen in terms 
of bond alternations as struct1 = (=-=-=)n and struct2 = (-=-=-)n. They both 
consist of a linear combination of partial wavefunctions describing 
wave1 = (=-=-=)n and wave2 = (-=-=-)n (in VB theory).

If I'm not mistaken wave1 and wave2 are resonance (canonics ?) structures and 
should therefore be written as wave1 <--> wave2. On the other hand, struct1 
and struct2 are different molecular structures and they should therefore be 
written as struct1 <==> (i.e. as a chemical equilibrium). I believe these 
structures are called bondisomers.

Each of these structures can thus be given by A*wave1+B*wave2.

I would like your opinion on this and would like to get advise on the accurate 
nomenclature of structs and waves.

I will summerize

Thanks
Serge