Skip to main content
. Author manuscript; available in PMC: 2014 Oct 24.
Published in final edited form as: J Phys Chem B. 2013 May 30;117(42):10.1021/jp4020146. doi: 10.1021/jp4020146

Table 2.

Summary of the calculated BLYP//6-31G*/MM, B3LYP//6-31G*/MM and B3LYP//6-31G*(COSMO) activation free energies a

System Method ζ or R2, R1 ΔG‡ Description Figure
PO3(−) with 1 QM H2O
22 A SCAAS		 Δg(ζ, R2) 1W PT; BLYP//6-31G*/MM ζ = −0.16, ~1.8 6.5(+21.0)b TS 1W PT Figure 9 (A)
PO3(−) with 2 QM H2O
22 A SCAAS		 2D-FES in ζ 1, ζ 2 space; 2W PT; BLYP//6-31G*/MM ζ = −0.10, ~1.8 1.4(+21.0)b TS 2W PT Figure 9(B)
PO3(−) with 1 QM H2O
22 A SCAAS nonpolar solvent		 2D-FES in ζ, R2 space; 1W PT, B3LYP//6-31G*/COSMO ζ = −0.14 14(+21)c TS 1W PT Figure 10A)
PO3(−) with 2 QM H2O
22 A SCAAS nonpolar solvent		 2D-FES in ζ 1, ζ 2 space for 2W PT, B3LYP//6-31G*/COSMO ζ = −0.10 1.4(+21)c TS 2W PT Figure 10(B)
MHDP with 2 QM H2O (20 Q atoms) COSMO solvent
22 A SCAAS nonpolar solvent		 2D-FES in R1, R2 space for P-O break, B3LYP//6-31G*/COSMO 2.0, 3.2 21 plateau Figure 11(A)
2D-FES in ζ, R2 space for 1W PT, B3LYP//6-31G*/COSMO 1.88, −0.15 15(+21) TS 1W PT Figure 13(A)
2D-FES in ζ1, ζ2 space for 2W PT, B3LYP//6-31G*/COSMO 3(+21) Figure 15
MHDP with 2 QM H2O (20 Q atoms)
22 A SCAAS		 2D-FES in R1, R2 space for P-O break, B3LYP//6-31G*/MM 2.0, 3.2 21 plateau Figure 11(B)
2D-FES in ζ, R2 space for 1W PT, B3LYP//6-31G*/MM 1.88, −0.15 12.3(+21) TS 1W PT Figure 13(B)
2D-FES in ζ1, ζ2 space for 2W PT, B3LYP//6-31G*/MM 1.88, −0.20 1.4(+21) TS 2W PT Figure 14(B)
MDP with Mg2+ and 6 QM H2O
32 Q atoms
18 A SCAAS		 2D-FES in ζ, R2 space for 1W PT, B3LYP//6-31G*/MM 1.88, −0.15 18(+22.5) TS 1W PT Figure 17
MDP with Mg2+ and 16 QM H2O
62 Q atoms
18 A SCAAS		 2D-FES in R1-R2 space for P-O break, B3LYP//6-31G*/MM dd=0.25 22.5 plateau Figure 12
a

Energies in kcal/mol. SCAAS and FES designate, respectively, the surface constraint all atom model57 and free energy surface (Potential of Mean Force). The reported activation free energies (relative to the RS) do not include the NQM corrections that will be added in Table 3.

b

Using the estimate for the height of the INT found for MHDP with 2 H2O (assuming that R1 reaches infinity)

c

Using the estimate of the height of the plateau found for MDP with 16 H2O (assuming that R1≫1)