Table 3. Pseudorotation Phases Pθ, Pucker Amplitudes Ar, and Relative Energies ΔE of Minima (MIN) and Transition States (TS) of DNA Nucleosides.
| MIN1 |
MIN2 |
TS1 |
TS2 |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pθ (deg) | Ar (deg) | ΔE (kcal/mol) | Pθ (deg) | Ar (deg) | ΔE (kcal/mol) | Pθ (deg) | Ar (deg) | ΔE (kcal/mol) | Pθ (deg) | Ar (deg) | ΔE (kcal/mol) | ||
| dA | MP2a | 358.7 | 34.3 | 2.9 | 189.8 | 34.7 | 0.0 | 83.7 | 40.6 | 4.5 | 295.0 | 13.4 | 4.9 |
| B3LYPb | 13.6 | 33.1 | 1.8 | 187.3 | 32.6 | 0.0 | 75.4 | 37.2 | 2.2 | 300.4 | 13.1 | 3.0 | |
| DFTB3 | 347.0 | 23.4 | 0.6 | 194.6 | 28.3 | 0.0 | 66.5 | 28.6 | 1.1 | 289.1 | 8.1 | 0.9 | |
| AM1/d | 281.5 | 11.3 | 0.0 | – | – | – | – | – | – | – | – | – | |
| dG | MP2a | 357.8 | 33.9 | 3.1 | 190.6 | 34.8 | 0.0 | 83.2 | 40.4 | 4.7 | 293.7 | 14.2 | 5.0 |
| B3LYPb | 18.1 | 33.8 | 1.9 | 186.8 | 33.1 | 0.0 | 74.3 | 37.0 | 2.4 | 300.3 | 13.5 | 3.2 | |
| DFTB3 | 345.1 | 23.4 | 0.7 | 195.3 | 28.6 | 0.0 | 67.8 | 28.3 | 1.3 | 290.8 | 8.9 | 1.0 | |
| AM1/d | – | – | – | 269.5 | 11.9 | 0.0 | – | – | – | – | – | – | |
| dC | MP2a | 36.8 | 37.5 | 2.8 | 180.2 | 35.4 | 0.0 | 89.6 | 39.9 | 3.9 | 344.2 | 3.6 | 4.9 |
| B3LYPb | 40.9 | 35.2 | 1.5 | 179.3 | 33.3 | 0.0 | 81.4 | 37.1 | 1.7 | – | – | – | |
| DFTB3 | 353.1 | 18.4 | 0.5 | 190.3 | 27.1 | 0.0 | 91.4 | 29.0 | 1.1 | 282.6 | 4.2 | 0.7 | |
| AM1/d | 292.8 | 9.6 | 0.0 | – | – | – | – | – | – | – | – | – | |
| dT | MP2a | 26.5 | 33.5 | 3.2 | 180.8 | 35.4 | 0.0 | 90.6 | 38.3 | 4.5 | 4.9 | 3.4 | 5.0 |
| B3LYPb | 38.6 | 34.1 | 1.7 | 180.1 | 33.3 | 0.0 | 85.4 | 35.9 | 2.1 | – | – | – | |
| DFTB3 | 354.9 | 17.3 | 0.7 | 189.3 | 27.5 | 0.0 | 95.2 | 22.5 | 1.7 | 310.2 | 4.0 | 0.8 | |
| AM1/d | 277.0 | 7.9 | 0.0 | – | – | – | – | – | – | – | – | – | |
a
MP2/6-311++G(3df,2p)//MP2/6-31++G(d,p).
b
B3LYP/6-311++G(3df,2p)//B3LYP/6-31++G(d,p).