CCL:G: Carbocation calculations, an approach
- From: Pedro Silva <pedros-*-ufp.edu.pt>
- Subject: CCL:G: Carbocation calculations, an approach
- Date: Wed, 23 Mar 2011 20:07:25 +0000
Your reaction is:
A+B -> C
Therefore the reaction energy
Energy(C) -Energy(A+B), which (neglecting BSSE) is equal to
energy (C) -(energy (a) + energy (b) ) =
-390.92315 - (-195.60813
+ (-195.27260) ) = -0.04242 hartree = -26.6 kcal.mol-1
"Exploring Chemistry with electronic structure Methods" is a
good book to start understanding computational chemistry. It used to be
distributed along with Gaussian, so probably there is a copy somewhere in your
On Tue, Mar 22, 2011 at 10:15 PM,
Miguel Quiliano Meza rifaximina===gmail.com <owner-chemistry[*]ccl.net>
My apologies if I disturb you with a couple of questions.
I have never worked with carbocations, but now I have a good case to
I would like to answer some chemicals questions using computational
chemistry, but unfortunately 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:
is the most probable to happen?
*What energy is necessary to
reach transitional compounds before obtained products?
I have performed
some calculations using this:
opt=tight freq b3lyp/6-31+g scf=qc with the respect spin multiplicity,
but my calculations told me that compound A is most stable than B,
besides compound C
is most stable than A and B. I stopped here because I think that is
A: is a carbocation very similar in structure like
B is not a carbocation
C is a carbocation product of
Final energy for A = -195.60813
Final energy for B = -195.27260
Final energy for C = -390.92315
Thank in advance for your time. Maybe if
you don´t have time please recommen me one good paper or good
Universidade Fernando Pessoa