Anthracene energy-level diagram

Figure 4. Electronic energy level diagram for anthracene illustrating the photophysical transitions (including reaction with the initiator from both the singlet and triplet states) and the associated kinetic constants.

Figure 4.4 Energy-level diagram showing how the electronic and vibrational energy levels in the ground-state (S0) and first excited-state (Si) anthracene molecule are related to the absorption and fluorescence emission spectra...

The dehydrodimerization reaction involving aromatic radical-cations is fast only when electron donating substituents are present in the benzene ring. These substituents stabilise the a-intermediate. Benzene, naphthalene and anthracene radical-cations form a a-sandwich complex with the substrate but lack the ability to stabilise the a-intermediate so that radical-cation substrate reactions are not observed. The energy level diagram of Scheme 6.4 illustrates the influence of electron donating substituents in stabilising the Wheland type a-intermediate. 

Fig. 2. Energy level diagram of rose bengal, chlorophyll, and anthracene in solution...

Delayed fluorescence from a very-short-lived upper excited singlet state populated by hetero-TTA has been observed for the first time using the system A = anthracene and X = xanthone (Nickel and Roden, 1982). An energy-level diagram for this system is shown in Figure 5.32, and the corrected spectrum of the delayed fluorescence of anthracene and xanthone in trichlorotrifluoroe-thane is depicted in Figure 5.33. The band at 36,000-40,000 cm has been assigned to the delayed fluorescence of anthracene produced by Tf +... 

Figure 5.32. Energy-level diagram of anthracene (A) and xanthone (X). Double lines denote the three different triplet pairs for which TTA processes are indicated asterisks mark the delayed fluorescence (DF) resulting from hetero-TTA (by permission from Nickel and Roden, 1982).

Figure 2.19. Energy level diagram for the Ru"/Os" molecular dyads having bridging phenylene-, naphthalene-, or anthracene-based units.

Figure 1.7. Orbital energy diagrams of anthracene and phenanthrene. For each HMO energy level the irreducible representation of the n MO is given.

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