CCL: DFT and dispersion

 Sent to CCL by: "Stefan  Grimme" [grimme\a/thch.uni-bonn.de]
 >First, I would like to thank all of you for your comments and help. I
 >strongly believe in the principle of getting the right answers for the right
 >reasons, which is why I want to make sure I am using methods in the context
 >they were developed for. With regards to solution corrections: As the DFT-D3
 >model is only geometry-dependent, I guess the following procedure would be
 >valid:
 >1. Optimize the geometry in the gas phase
 >2. Calculate energy in solution (e.g. using SMD)
 >3. Add DFT-D3 dispersion correction
 >4. Add thermal corrections
 >Would you agree?
 Basically yes but I would also use the dispersion correction for the geometry
 optimization as well. Structures of 'normal' molecules are less affected by
 dispersion than energies but conformations are sometimes sensitive to details in
 the potential.
 Cheers!
 Stefan Grimme (grimme a thch.uni-bonn.de)