Electronic structures of C60 adsorbed on Si(111)-(7 × 7) and Si(001)-(2 × 1) surfaces

K. Sakamoto, D. Kondo, M. Harada, A. Kimura, A. Kakizaki, S. Suto

Research output: Contribution to journalConference articlepeer-review

15 Citations (Scopus)

Abstract

We have investigated the electronic structures of C60 molecules adsorbed on the Si(111)-(7 × 7) and Si(001)-(2 × 1) surfaces using photoelectron spectroscopy. The coverage-dependent valence band spectra show that the highest occupied molecular orbital (HOMO) of a C60 molecule splits into two peaks on both surfaces at a coverage of less than 0.25 monolayer. These split peaks are assigned to be the shifted HOMO and the bonding state with the polarization-dependent measurements. The binding energies of the molecular orbitals and the C 1s core level show a small shift on the Si(001)-(2 × 1) surface and no shift on the Si(111)-(7 × 7) surface with decreasing the coverage. These results indicate that the strong interaction between C60 molecules and the surfaces have a covalent character on the Si(111)-(7 × 7) surface, and both covalent and ionic characters on the Si(001)-(2 × 1) surface. We attribute the difference in the charge states of C60 molecules to the different surface structures.

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Electronic structures of C<sub>60</sub> adsorbed on Si(111)-(7 × 7) and Si(001)-(2 × 1) surfaces'. Together they form a unique fingerprint.

Cite this