Solvation Model SMD with a scaled solvent-accessible-surface for pKa calculation


Click here for full thread
Clicked A Few Times
Dear Nwchem developers.

I was reading about pKa's calculation on a paper from The Journal of Physical Chemistry April 2018 titled: Quantum Chemical Calculation of pKas of Environmentally Relevant Functional Groups: Carbox.... According to that document the original SMD model show errors of 6?10 pK units in Carboxylic Acids, Amines, and Thiols. A modification was made in the SMD model (SMD_scaled-solvent-accessible-surface). Now using M06-2X density functional approximation and 6-31+G(d,p) basis set it is possible to calculate the pKas of those problematic functional groups with greater precision.

The mean unsigned errors with this new approach are the following: 0.9 pK units for carboxylic acids, 0.4 pK units for aliphatic amines and 0.5 pK units for thiols.

Could you implement this new Solvation Model's approach, bassed in SMD_scaled-solvent-accessible-surface in Nwchem?

Best regards, A.G