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Optical Properties

  • Yoshinori Tokura
  • Kazuhiko Seki

Abstract

The optical and photoelectronic properties of molecular systems essentially reflect the individual electronic states of constituent molecules. Nevertheless, some important modifications show up occasionally in optical and photoelectron spectra of molecular solids due to intermolecular interaction or the delocalization effect of electrons extended over molecular units. In the ordinary optical spectra, the Coulombic effect, or the final-state interaction, is important in the optical excitation process because of the localized or low-dimensional nature of electronic structures. This Coulombic effect results in the dominant role of the excitons, as explained in the following sections. Photoelectron spectroscopy, however, gives one-particle spectra which contain a lot of information about the π - or σ-valence electrons extending over the molecular units. In some cases, spectral variation reveals important information about the local configuration of molecular units which would otherwise be difficult to establish.

Keywords

High Occupied Molecular Orbital Polarization Energy Molecular Solid NEXAFS Spectrum Molecular Excitation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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© Springer-Verlag Tokyo 1998

Authors and Affiliations

  • Yoshinori Tokura
  • Kazuhiko Seki

There are no affiliations available

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