From owner-chemistry "-at-" ccl.net Thu Dec 13 12:07:01 2007
From: "Sergio Emanuel Galembeck segalemb#usp.br" <owner-chemistry##server.ccl.net>
To: CCL
Subject: CCL: Strange NBO DEL Calculation Results
Message-Id: <-35842-071213102703-7283-F7JWvtaVvBygSrJ0Tcblwg##server.ccl.net>
X-Original-From: Sergio Emanuel Galembeck <segalemb##usp.br>
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Date: Thu, 13 Dec 2007 13:26:37 -0200
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Sent to CCL by: Sergio Emanuel Galembeck [segalemb]*[usp.br]
Hello,

   It's a good question: how does NBO choose a resonance structure? I sugges=
t
that we can ask Professor Weinhold. He is a kind person and always gives
helpfull sugestions.

                   Best regards,

                              Sergio Galembeck

Citando "Hemant Srivastava hemantkrsri,,gmail.com" <owner-chemistry+/-ccl.net>=
:

>
> Sent to CCL by: "Hemant Srivastava" [hemantkrsri*o*gmail.com]
> Dear Friends,
>
> I am doing NBO Del calculations, the input file is as follows
>
> --------------------------------------------------------------------------=
---------------------------------
> %chk=3Dc_cyc_6_reac_res1.chk
> %mem=3D120MW
> # HF/6-31g* scrf=3D(solvent=3Dwater,read,pcm)  pop=3D(full,nbodel)
>
> choose resonance structure-1
>
> 0 1
>  X=09Y=09Z
>
> Radii=3DUAHF
>
> $NBO NBO $END
> $Choose
> LONE
> a 1
> b 2
> end
> BOND S 1 2
>      =09S 3 5
> end
> $END
> $del nostar
> $End
>
> --------------------------------------------------------------------------=
-------------------------------------------
>
> I have made four different resonance structure of the same molecule
> and calculated deletion energies. Surprisingly I am getting the NBO
> default resonance structure higher in deletion energy than two of the
> structures I choose. Does anyone know if it make sense. Following is
> the energy of deletions of all four resonance structures.
>
> Resonance Structure-1=09Energy of deletion : =09-1509.149678811
> Resonance Structure-2=09Energy of deletion :=09-1509.102611727
> Resonance Structure-3=09Energy of deletion : =09-1509.131159010
> Resonance Structure-4=09Energy of deletion : =09-1509.117304249 (Default =
=20
>  Structure)
>
> Thanks in advance
>
> Hemant Srivastava
> The Hebrew University of Jerusalem
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>
>
>
> -=3D This is automatically added to each message by the mailing script =3D=
->
>
>