Table 2. Energy Levels of HOMO and LUMO, Energy Gap (Eg), and Change of Energy Gap (ΔEg) upon the Drug Adsorption on the Aun (n = 6, 8, and 20) Clustersa.
| species | in vacuum |
in water |
||||||
|---|---|---|---|---|---|---|---|---|
| HOMO | LUMO | Eg | ΔEg | HOMO | LUMO | Eg | ΔEg | |
| Au6 | –5.9 | –3.9 | 2.0 | –5.4 | –3.1 | 2.3 | ||
| Au8 | –5.8 | –4.4 | 1.4 | –5.3 | –3.7 | 1.6 | ||
| Au20 | –5.7 | –3.9 | 1.8 | –5.1 | –3.2 | 1.9 | ||
| STZ_1 | –5.4 | –1.9 | 3.4 | –5.4 | –2.0 | 3.4 | ||
| STZ_2 | –5.0 | –1.5 | 3.5 | –5.1 | –1.8 | 3.3 | ||
| STZ– | –4.4 | –1.3 | 3.1 | |||||
| Au6·STZ_1 | –4.8 | –3.1 | 1.7 | –15.0 | –4.9 | –3.0 | 1.9 | –17.4 |
| Au8·STZ_1 | –5.1 | –3.5 | 1.6 | 14.3 | –5.1 | –3.4 | 1.7 | 6.3 |
| Au20·STZ_1 | –5.4 | –3.8 | 1.6 | –12.8 | –4.8 | –3.2 | 1.7 | –11.6 |
| Au6·STZ–_1 | –4.8 | –2.9 | 1.9 | –17.4 | ||||
| Au8·STZ–_1 | –4.8 | –3.3 | 1.5 | –6.3 | ||||
| Au20·STZ–_1 | –4.7 | –3.2 | 1.6 | –17.7 | ||||
a
The results are obtained at the PBE/cc-pVTZ/cc-pVDZ-PP level and are given in eV, except for ΔEg (%).