Table 2.
TD-ωb97xd-PCM/6-31G(3df,p) calculated vertical lowest lying transition energies (ΔE) in eV, and oscillator strength (f) of G•+-C base pair. Structure is shown in scheme 1(a). See Figure S1 in the supporting information for MOs involved in transitions.
| State | Transitiona | ΔE (eV) |
λ (nm) |
f | Contribution | Red-shift 40 nm | Exp. (nm)c |
|
|---|---|---|---|---|---|---|---|---|
| ΔE (eV) | λ (nm) | |||||||
| D1 | GC(n)→G(π*)b | 2.31 | 536 | 0.0003 | 97% b | 2.15 | 576 | |
| D2 | G(π)→G(π*) | 2.59 | 479 | 0.0100 | 78% | 2.39 | 519 | |
| D3 | G(π)→G(π*) | 2.94 | 422 | 0.0377 | 65% | 2.68 | 462 | 480, 470–550 |
| D4 | GC(n)→G(π*) b | 3.00 | 413 | 0.0000 | 66% | 2.74 | 453 | |
| D5 | C(π)→G(π*) | 3.34 | 372 | 0.0136 | 94% | 3.01 | 412 | |
| D6 | G(π)→G(π*) | 3.54 | 351 | 0.1148 | 86% | 3.17 | 391 | 400, 385 |
| D7 | C(π)→G(π*) | 3.64 | 341 | 0.0017 | 88% | 3.25 | 381 | |
| D8 | C(π)→GC(π*) GC(π)→GC(π*) b |
3.68 | 337 | 0.0000 | 71% | 3.29 | 377 | |
| D9 | G(n) →G(π*) | 3.83 | 324 | 0.0000 | 75% | 3.41 | 364 | |
| D10 | GC(n) →G(π*) b | 4.29 | 289 | 0.0000 | 88% | 3.77 | 329 | |
| D11 | GC(π)→ G(π*) b | 4.50 | 275 | 0.1272 | 71% | 3.94 | 315 | 300 |
| D12 | C(π)→ GC(π*) b | 4.59 | 270 | 0.0000 | 50% | 4.00 | 310 | |