Hi Folks,

I’m about to do some calculations using the Counterp= oise keyword in G09.=A0 I need some help in calculating the binding energy = of my complex from the output. I know, for example, how and where to find t= he counterpoise corrected energy, and I know that the binding energy is

&nb= sp;

counter= poise corrected energy of complex – counterpoise corrected energy fra= gment 1 – counterpoise corrected energy fragment 2.=

What I don’t kno= w is where to find the counterpoise corrected energy of the fragments in th= e Gaussian 09 or Gaussian 03 output.=A0 I would greatly appreciate it if so= meone could help me with this (the Gaussian User’s Reference isn̵= 7;t much help since it doesn’t show the output.)=A0 I would especiall= y help if someone could attach at least a portion of an output file which i= ncludes the counterpoise corrected energies of the fragments and the comple= x, so I can see where they are in a real case.

Thank you very much for your help= .

Sam=

Samu= el A. Abrash
Department of Chemistry
University of Richmond
Richmo= nd, VA 23173
Phone:=A0 804-289-8248
Fax:=A0 804-287-1897
E-mail:= =A0 sabr= ash]*[richmond.edu
Web-page:=A0 http://www.richmond.edu/~sabr= ash

"In 1893&= nbsp;Charles Hinton left Japan to become a mathematics instructor at P= rinceton University, where he invented a baseball-pitching machine tha= t used gunpowder to propel the balls, like a cannon. After several ac= cidents, the device was abandoned and Hinton lost his job ..." Terry P= ratchett, Ian Steward and Jack Cohen, The Science of Diskworld III

&nbs= p;

From: owner-chemistry+sabras= h=3D=3Drichmond.edu]*[ccl.net [mailto:owner-chemistry+sabrash=3D=3Drichmond.e= du]*[ccl.net] On Behalf Of Miguel Quiliano Meza rifaximina=3D=3D=3Dgma= il.com
Sent: Tuesday, March 22, 2011 6:15 PM
To: Abrash= , Sam
Subject: CCL: Carbocation calculations, an approach

Dear colleagues.

My apologies= if I disturb you with a couple of questions.

I have never worked wi= th carbocations, but now I have a good case to start

I would like to= answer some chemicals questions using computational chemistry, but unfortu= nately I obtained rare energy values.

Could you tell me please, what= should I do? or what kind of chemistry model should I use?.

I want= to answer some questions:

*Which reaction is the most probable to h= appen?
*What energy is necessary to reach transitional compounds before = obtained products?

I have performed some calculations using this:
# opt=3Dtight freq b3lyp/6-31+g scf=3Dqc with the respect spin m= ultiplicity, but my calculations told me that compound A is most stable tha= n B, besides compound C is most stable than A and B. I stopped here because= I think that is impossible.

A: is a carbocation very similar in str= ucture like B
B is not a carbocation
C is a carbocation product= of A+B

Final energy for A =3D -195.60813

Final energy for B = =3D -195.27260

Final energy for C =3D -390.92315

Thank in adv= ance for your time. Maybe if you don=B4t have time please recommen me one g= ood paper or good tutorial.

Best regards.
Miguel.