林昶廷-第11週作業1212
Please use ChatGPT to explore a thematic series of questions within the scope of computational chemistry and follow up with further inquiries about any unfamiliar terms ( except homework )
- Calculate the first 2 excited states of the Oxygen atom by using the CASSCF method with appropriate basis sets then compare with the experimental values.
| CASSCF | basis set | Energy( eV ) | ABS |
| 3P to 1D | 6-31+G** | 2.03 | 0.06 |
| d-aug-cc-pVDZ | 2.02 | 0.27 | |
| d-aug-cc-pVQZ | 2.02 | 0.25 | |
| Experimental | 1.97 | ||
| 1D to1S | 6-31+G** | 1.75 | 0.47 |
| d-aug-cc-pVDZ | 1.77 | 0.45 | |
| d-aug-cc-pVQZ | 1.95 | 0.27 | |
| Experimental | 2.22 |
- For 7-Azaindole there have normal form & tautomer form two different structures,Which one is more stable at ground state
Unit:hartree
| 7-Azaindole | E(Hartree) |
| normal form | -379.87234 |
| tautomer form | -379.85166 |
| TS | -379.68897 |
normal form 的能量較低，較穩定
- Will there has Transition State ( TS ) between the two structures? If so, what would be the barrier height between them?
 |
 |
 |
| normal mode | Transiton state | tautomer |
Table.2 barrier height Unit:hartree
| 7-Azaindole | E |
| normal form | -379.87234 |
| TS | -379.68897 |
| tautomer form | -379.85166 |
| barrier height | 0.183376 |
| barrier height | 4.98979(eV) |
- Optimize the first excited state of two structures, and plot a simple energy level diagram based on the energy difference.
- Calculate the verticle excitation energy between the ground state & first excited state.
Refence: NIST Atomic Spectra Database