Table 2.

The contributions to the free energy of solvation: polarization energy$\mathrm{\Delta }{E}_{\mathit{\text{QM}}}^{\mathit{\text{pol}}}({\mathbf{Q}}_{\mathit{\text{gas}}}^0\to {\mathbf{Q}}_{\mathit{\text{PCM}}}^0),$ hydrophobic (Hdr) and van der Waals (vdW) contributions to ΔG_cav, classical AC solvation free energy $\mathrm{\Delta }{G}_{\mathit{\text{sol}}}(\mathbf{Q}=0\to {\mathbf{Q}}_{\mathit{\text{PCM}}}^0)$ and the LRA terms of Eg. (9). The final solvation free energy ΔG_sol is calculated using Eq. (7). For comparison, the corresponding ΔG_sol values obtained with the PCM model are reported. All energies in kcal/mol.

			ΔGcav		Terms of Eq. (9)		ΔGsol
Tautomer	$\mathrm{\Delta }{E}_{\mathit{\text{QM}}}^{\mathit{\text{pol}}}({\mathbf{Q}}_{\mathit{\text{gas}}}^0\to {\mathbf{Q}}_{\mathit{\text{PCM}}}^0),$	$\mathrm{\Delta }{G}_{\mathit{\text{sol}}}(\mathbf{Q}=0\to {\mathbf{Q}}_{\mathit{\text{PCM}}}^0)$	Hdr	vdW	${\langle \rangle }_{E(\mathbf{Q})}$	${\langle \rangle }_{E({\mathbf{Q}}_{\mathit{\text{PCM}}}^0)}$	This study	PCM
U0−	5.62	−71.59	6.30	−4.49	−2.12	−1.16	−65.80	−65.64
U1−	7.35	−73.29	6.35	−4.31	−3.43	−2.57	−66.90	−66.22
U2−	10.63	−84.76	6.33	−4.29	−3.44	−2.58	−75.10	−73.59
U3−	6.48	−79.75	6.31	−4.30	−0.90	−0.21	−71.81	−68.25
U4−	21.12	−93.03	6.35	−4.32	−0.03	−9.22	−79.50	−86.47