High energy-resolution electron energy-loss spectroscopy study of the electronic structure of C60 polymer crystals

M. Terauchi, S. Nishimura, Y. Iwasa

Research output: Contribution to journalArticlepeer-review

9 Citations (Scopus)

Abstract

Electronic structures of C60 polymer crystals (dimerized C 60: dimer-C60, one-dimensionally polymerized C 60: 1D-C60 and two-dimensionally polymerized C 60: 2D-C60) were studied by using a high energy-resolution electron energy-loss spectroscopy microscope. Spectra were obtained from single crystalline specimen areas of 180 nm in diameter. The dielectric functions of the materials were derived from valence electron excitation spectra by using Kramers-Kronig analysis. The onset energies of the imaginary parts of the dielectric functions ε2 (bandgap energies) were 1.6 eV (dimer-C60), 1.4 eV (1D-C60) and 1.5 eV (2D-C 60). Those energies are smaller than that of the monomer C 60 (mono-C60) crystal of 1.7 eV. Energies of interband transition peaks observed in each ε2 of polymerized C 60 material were smaller by amounts of 0.5 eV than those of corresponding peak energies of mono-C60. Excitation spectra of 1s electrons to the conduction band showed that the intensity of 1s → π* transitions compared to that of 1s → σ* transitions was smaller than that of mono-C60. It may due to that a part of π-bonds of a C60 cluster changed to σ-bonds to form covalent bonds with neighboring C60 clusters in the polymerization process.

Original languageEnglish
Pages (from-to)167-172
Number of pages6
JournalJournal of Electron Spectroscopy and Related Phenomena
Volume143
Issue number2-3 SPEC. ISS.
DOIs
Publication statusPublished - 2005 May

Keywords

  • Carbon 1s excitation spectra
  • Dielectric functions
  • EELS spectroscopy
  • Interband transitions
  • Poly C
  • π-Plasmon

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Radiation
  • Atomic and Molecular Physics, and Optics
  • Condensed Matter Physics
  • Spectroscopy
  • Physical and Theoretical Chemistry

Fingerprint Dive into the research topics of 'High energy-resolution electron energy-loss spectroscopy study of the electronic structure of C<sub>60</sub> polymer crystals'. Together they form a unique fingerprint.

Cite this