Table 1. Comparison of TDDFT, CC2, and Experimental Excitation Energies [eV] (Wavelengths [nm] Are in Parentheses) for the La and Lb States in the Linear Acenesa.
| number of rings | B3LYP (a0 = 0.20) | B3LYPopt (a0 = 0.50) | CAM-B3LYP (α + β = 0.65) | LC-BOP (μ = 0.29) | LC-PBE (μ = 0.29) | LC-ωPBE (μ = 0.29) | LC-BLYP (μ = 0.29) | CC2 | experiment(20) |
|---|---|---|---|---|---|---|---|---|---|
| La state | |||||||||
| 2 | 4.39 (282) | 4.69 (264) | 4.68 (265) | 4.76 (260) | 5.05 (246) | 4.80 (258) | 4.76 (260) | 4.89 (254) | 4.66 (266) |
| 3 | 3.22 (385) | 3.54 (350) | 3.54 (350) | 3.64 (341) | 3.66 (339) | 3.67 (338) | 3.63 (342) | 3.70 (335) | 3.60 (344) |
| 4 | 2.44 (508) | 2.75 (451) | 2.77 (448) | 2.89 (429) | 2.89 (429) | 2.91 (426) | 2.88 (431) | 2.90 (428) | 2.88 (431) |
| 5 | 1.89 (656) | 2.19 (566) | 2.22 (558) | 2.36 (525) | 2.36 (525) | 2.38 (521) | 2.35 (528) | 2.35 (528) | 2.37 (523) |
| 6 | 1.49 (832) | 1.77 (700) | 1.83 (438) | 1.97 (629) | 1.98 (626) | 1.99 (623) | 1.96 (633) | 1.95 (636) | 2.02 (614) |
| 7 | 1.18 (1051) | 1.46 (849) | 1.53 (810) | 1.68 (738) | 1.69 (734) | 1.71 (725) | 1.68 (738) | 1.66 (747) | |
| MAE (eV) | 0.42 | 0.13 | 0.11 | 0.04 | 0.10 | 0.06 | 0.04 | 0.09 | |
| Lb state | |||||||||
| 2 | 4.48 (277) | 4.75 (261) | 4.63 (268) | 4.59 (270) | 4.62 (268) | 4.61 (269) | 4.59 (270) | 4.47 (277) | 4.13 (300) |
| 3 | 3.87 (320) | 4.14 (299) | 4.04 (307) | 4.02 (308) | 4.04 (307) | 4.03 (308) | 4.02 (308) | 3.90 (318) | 3.64 (341) |
| 4 | 3.48 (357) | 3.73 (332) | 3.66 (339) | 3.65 (340) | 3.67 (338) | 3.66 (339) | 3.65 (340) | 3.52 (352) | 3.39 (366) |
| 5 | 3.21 (386) | 3.46 (358) | 3.40 (365) | 3.40 (365) | 3.41 (364) | 3.41 (364) | 3.39 (366) | 3.27 (379) | 3.12 (397) |
| 6 | 3.02 (411) | 3.26 (380) | 3.21 (386) | 3.22 (385) | 3.23 (384) | 3.23 (384) | 3.22 (385) | 3.09 (401) | 2.87 (432) |
| 7 | 2.88 (431) | 3.11 (399) | 3.08 (403) | 3.09 (401) | 3.10 (400) | 3.10 (400) | 3.08 (403) | 2.97 (417) | - |
| MAE (eV) | 0.18 | 0.44 | 0.36 | 0.35 | 0.36 | 0.36 | 0.34 | 0.22 | - |
a
The mean absolute errors (MAE) relative to solvent-corrected experimental results are listed below each of the various methods. Excitation energies were computed with the cc-pVTZ basis with the same reference geometry for all of the different methods.