Performance of SM8 on a test to predict small-molecule solvation free energies.
The SM8 quantum mechanical aqueous continuum solvation model is applied to a 17-molecule test set proposed by Nicholls et al. (J. Med. Chem. 2008, 51, 769) to predict free energies of solvation. With the M06-2X density functional, the 6-31G(d) basis set, and CM4M charge model, the root-mean-square error (RMSE) of SM8 is 1.08 kcal mol(-1) for aqueous geometries and 1.14 kcal mol(-1) for gas-phase geometries. These errors compare favorably with optimal explicit and continuum models reported by Nicholls et al., having RMSEs of 1.33 and 1.87 kcal mol(-1), respectively. Other models examined by these workers had RMSEs of 1.5-2.6 kcal mol(-1). We also explore the use of other density functionals and charge models with SM8 and the RMSE increases to 1.21 kcal mol(-1) for mPW1/CM4 with gas-phase geometries, to 1.50 kcal mol(-1) for M06-2X/CM4 with gas-phase geometries, and to 1.27-1.64 kcal mol(-1) with three different models at B3LYP gas-phase geometries.
Chamberlin
Adam C
AC
Department of Chemistry and Research Computing Center, 207 Pleasant Street SE, University of Minnesota, Minneapolis, Minnesota 55455-0431, USA.
Cramer
Christopher J
CJ
Truhlar
Donald G
DG
D000465:Algorithms; D003198:Computer Simulation; D004735:Energy Transfer; D005740:Gases; D008956:Models, Chemical; D009930:Organic Chemicals / Q000737:chemistry*; D011789:Quantum Theory; D012995:Solubility; D012997:Solvents / Q000737:chemistry*; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
D005740:Gases; D009930:Organic Chemicals; D012997:Solvents; D014867:Water