| Abstract
| - The results of time-dependent density functional theory (TD-DFT) calculations of the transition energies andoscillator strengths of the excited states of formaldehyde, benzene, ethylene, and methane are reported. Thelocal DFT (LDFT) transition energies tend to be smaller than experimental values by 0.1−1.3 eV. Inclusionof nonlocal (NLDFT) (gradient corrected) effects made the calculated energies larger than the LDFT valuesand thus made the energies closer to the experimental values for formaldehyde, ethylene, and methane. Forbenzene, no significant change in the calculated transition energies due to the addition of nonlocal effectswas observed. The TD-DFT oscillator strengths are much better than those found at the configuration interactionsingles (CIS) level. The agreement between the calculated TD-DFT values and the experimental values forthe oscillator strengths is quite good, at least semiquantitative at both the LDFT and NLDFT levels.
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