Table 5. Comparison of aspherical atom model derived X—H bond lengths with reference neutron diffraction data in terms of absolute difference (in mÅ).
HAR (±) represents HAR with the crystal environment represented via point multipoles and HAR for the version without such representation.
| B3LYP method | Hartree–Fock method | |||||||
|---|---|---|---|---|---|---|---|---|
| G-31G(d,p) basis set | cc-pVTZ basis set | |||||||
| Model | IAM | TAAM | THAM | THAM | HAR | HAR (±) | THAM | HAR (±) |
| C—H | ||||||||
| Carbamazepine | 90 | 17.5 | 11 | 7.8 | 6.7 | 5.1 | 5.9 | 6.7 |
| Gly-L-Ala | 118 | 8.1 | 9.1 | 9.6 | 6.4 | 7.3 | 11.0 | 13.1 |
| NAC·H2O | 134 | 32.5 | 21.2 | 19.8 | 18.2 | 14.9 | 15.1 | 11.7 |
| Xylitol | 130 | 9.4 | 11.8 | 12.5 | 11.3 | 8.8 | 13.9 | 9.6 |
| O—H, N—H | ||||||||
| Carbamazepine | 157 | 44.5 | 34.8 | 30 | 26.1 | 18.6 | 12.0 | 6.7 |
| Gly-L-Ala | 143 | 31.7 | 17 | 17 | 16.9 | 7 | 11.9 | 14.5 |
| NAC·H2O | 138 | 71.3 | 51.2 | 58.8 | 52.1 | 40.1 | 31.0 | 16.7 |
| Urea | 98 | 18.5 | 16.3 | 9.9 | 9.9 | 3.6 | 5.7 | 9.6 |
| Xylitol | 124 | 50.9 | 33 | 35.2 | 29.6 | 17 | 7.9 | 9.0 |