Table 5.

Ligand solvation free energies in bulk water from QM ab initio methods with continuum solvation, MM-PMPB/SA and explicit solvent FEP simulations using the polarizable force field. ΔA_sol is the total ligand solvation free energies (kcal/mol) in bulk water including the polar (ΔA_sol,polar) and the non-polar components.

	$\mathrm{\Delta }{A}_{\mathit{\text{sol}}}^{MP2}$ 1	$\mathrm{\Delta }{A}_{\mathit{\text{sol}},\mathit{\text{polar}}}^{MP2}$ 1	$\mathrm{\Delta }{A}_{\mathit{\text{sol}}}^{DFT}$ 2	$\mathrm{\Delta }{A}_{\mathit{\text{sol}},\mathit{\text{polar}}}^{DFT}$ 2	$\mathrm{\Delta }{A}_{\mathit{\text{sol}}}^{PMPB}$ 3	$\mathrm{\Delta }{A}_{\mathit{\text{sol}},\mathit{\text{polar}}}^{PMPB}$ 3	$\mathrm{\Delta }{A}_{\mathit{\text{sol}}}^{FEP}$
A	−59.3	−64.6	−57.9	−59.1	−54.2	−56.8	−45.8
B	−55.8	−60.8	−57.1	−57.6	−55.6	−58.1	−71.7
C	−62.6	−67.6	−62.1	−62.6	−58.3	−60.9	−56.4
D	−58.6	−64.1	−56.0	−57.1	−53.4	−56.2	−47.1
E	−69.7	−75.4	−64.1	−65.1	−57.6	−60.1	−66.8

¹From MP2/6-31+G* with PCM implicit solvent model.

²From B3LYP/6-31G* with PCM model.

³MM-PMPB/SA approach.