Subject: CCL: Gaussian 03 Output Interpretation

From: Wayne Fisher <wfisher(at)utdallas.edu>
Date: Fri, 04 Jun 2004 10:20:53 -0500

Ladies and Gentlemen,

Below is a portion of the output from a Gaussian 03 DFT optimization
calculation on a molecule in a solvent using the pcm method.  What is
the "Total free energy in solution: with all non electrostatic terms"?
I can see that this is the sum of the electronic energy E(RB+HF-LYP) and
the cavitation, dispersion, and repulsion energies, but why is this
labeled a free energy?  At this point in the job no frequency
calculation has yet been done and no entropy calculated as far as I can
tell.

Can anyone explain or point me to documentation that explains this
output?

**********
 Error on total polarization charges =  0.02091
 SCF Done:  E(RB+HF-LYP) =  -613.441845676     A.U. after   10 cycles
             Convg  =    0.2485D-08             -V/T =  2.0048
             S**2   =   0.0000
 KE= 6.105335890138D+02 PE=-1.734494797920D+03 EE= 3.688267374326D+02
 --------------------------------------------------------------------
 Variational PCM results
 =======================
 <psi(f)|   H    |psi(f)>                     (a.u.) =    -613.431671
 <psi(f)|H+V(f)/2|psi(f)>                     (a.u.) =    -613.441846
 Total free energy in solution:
  with all non electrostatic terms            (a.u.) =    -613.439088
 --------------------------------------------------------------------
 (Polarized solute)-Solvent               (kcal/mol) =      -6.38
 --------------------------------------------------------------------
 Cavitation energy                        (kcal/mol) =       8.63
 Dispersion energy                        (kcal/mol) =      -7.56
 Repulsion energy                         (kcal/mol) =       0.66
 Total non electrostatic                  (kcal/mol) =       1.73
 --------------------------------------------------------------------
*********

Thanks,

Wayne Fisher
wfisher-at-utdallas.edu
The University of Texas at Dallas