PCM calculation

If you have not already done so, you should take a look at the eT_launch page to get an understanding of how the launch script works.

Setting up a PCM calculation

A Polarizable Continuum Model (PCM) calculation is performed by specifying a HF or CC wave function in the method section of the input file. Moreover, you need to specify the pcm section specifying the keyword external if eT needs to read the parameters from an external .pcm-file or internal if you read the parameters from the eT input. If the parameters are internal it is then necessary to specify the solvent keyword (several are available, among others water, ethanol and toluene, more can be found in Valid keyword values). You can also specify the tesserae area and the solver type keywords, for instance:

- pcm
  input : internal
  solvent: water
  solver type : iefpcm
  tesserae area: 0.3

A minimal working example for an RHF single-point calculation of water in water solvent is:

- do
  ground state

- pcm
  input : internal
  solvent: water
  solver type : iefpcm
  tesserae area: 0.3

- method

- geometry
basis: cc-pVDZ
 O          0.009319    1.133156    0.000000
 H          0.023452    0.185621    0.000000
 H          0.906315    1.422088    0.000000

If the calculation exited successfully (look for eT terminated successfully! at the bottom of the file), the output file should show iteration information for the solver converging the Hartree-Fock equations in the PCM water solvent. The table with the iteration information should end with something like this:

  11           -76.035497980826     0.9736E-09     0.5684E-13
  12           -76.035497980826     0.5823E-09     0.4263E-13
  13           -76.035497980826     0.5326E-10     0.0000E+00
Convergence criterion met in 13 iterations!

And then you will find a summary of the HF parameters and the energestics of the QM/PCM solver

- Summary of RHF wave function energetics (a.u.):

   HOMO-LUMO gap:                  0.697569870135
   Nuclear repulsion energy:       9.307879526626
   Electronic energy:            -85.343377507452
   Total energy:                 -76.035497980826

- Summary of QM/PCM energetics:
                                       a.u.             eV     kcal/mol
   QM/PCM SCF Contribution:        -0.009387191610    -0.25544    -5.891
   QM/PCM Electrostatic Energy:    -0.018774383219    -0.51088   -11.781

Relevant input sections