Table 3.
Calculated Activation Barrier (in kcal/mol) for Diester Hydrolysis in the Active-Site Model of AP in the Gas Phase (see Fig. 1)
| Single Points at DFTB3 Geometries |
Single Points at B3LYP Geometries |
||||||
|---|---|---|---|---|---|---|---|
| Substrate | DFTB3 | B3LYP | M06 | MP2 | B3LYP | M06 | MP2 |
| MpNPP− | 8.8 | 9.2 (4.2a) 5.7 (3.1) | 7.6 | 12.0 (6.7) | 6.8 (6.1) | 8.8 | |
| MmNPP− | 9.7 | 9.2 (9.4) | 6.8 (7.5) | 13.6 | 15.3 (12.0) | 13.2 (12.8) | 13.2 |
| MPP− | 20.0 | 16.2 (9.1) | 11.6 (7.1) | 9.6 | 20.1 (11.6) | 13.0 (10.8) | 10.4 |
a
The number with parentheses is obtained with corresponding DFT functional plus D3 dispersion. The geometries are optimized either at DFTB3/3OB or B3LYP/6-31+G(d,p) level. Single point energy calculations are carried out at B3LYP, M06, and MP2 method at two levels of geometries using a larger basis set of 6-311++G(d,p).