Strongly Bound Frenkel Excitons on TiO₂ Nanoparticles: An Evolutionary and DFT Approach

Figure 7

UV-vis absorption spectra of NPs with . (a–f) Vertical lines represent the corresponding lowest transitions from the singlet ground state (S₀) to excited states S₁–S₅ (shown in relative magnitudes). (g, h) The main contribution of the molecular orbitals () in the excitation S₀→S₁ of (TiO₂)₂₀ and (TiO₂)₁₉.

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