Abstract
Our systematic investigation using field-ion scanning tunneling microscopy (FI-STM) is reviewed for the adsorption and film growth of fullerenes (C 60, C 70, C 80, and C 84) and metallofullerenes (Sc@C 74/Sc 2@C 74, Sc 2@C 84, Y@C 82, and Gd@C 82) on the Si(100)-2x1, Si(111)-7x7, GaAs(001)-2x4-As, Cu(111)1x1, and Ag(111)1x1 surfaces. The fullerene molecules are stable on the Si(100)-2x1 and Si(111)-7x7 surfaces at room temperature because of the strong bonding to the substrate dangling bonds. As a result, unique intramolecular structures of C 60 molecule are observed. The STM images of the C 84, Sc@C 74/Sc 2@C 74, and Sc 2@C 84 molecules are used to draw information on the molecular structures. In contrast to the Si surfaces, the fullerene molecules are mobile on the terrace of the metal surfaces and initially segregate to the step. A well-ordered two dimensional overlayer forms with a close-packed arrangement upon annealing the fullerene covered surfaces. On the Cu(111) surface, the commensurate (4x4) phase forms for the cases of the C 60, C 70 and C 60(X)C 70(1-X) adsorption, indicating a strong interaction between the Cu substrate and fullerenes. Beautiful intramolecular structures of the C 60 and C 70 molecules are observed and are interpreted as the local mappings of the electron density of states. One-dimensional cluster formation of C 60, Y@C 82, and Gd@C 82 on the step of the Cu(111)-1x1 surface is analyzed and the preferential dimer formation is only observed for the case of Y@C 82, which is attributed to the interaction between the unpaired electrons of the Y@C 82 molecules. On the Ag(111) surface, the C 60 and Sc 2@C 84 monolayer films show several phases that have an almost identical nearest neighbour distance but are rotated from each other. Among the systems studied, C 60 on the GaAs(001)-2x4-As surface shows a unique highly-strained fcc(110)-oriented multi-layer film growth, while all other systems show the well-known fcc(111)-oriented multi-layer growth.
| Original language | English |
|---|---|
| Pages (from-to) | 17-45 |
| Number of pages | 29 |
| Journal | Science Reports of the Rerearch Institutes Tohoku University Series A-Physics |
| Volume | 44 |
| Issue number | 1 |
| Publication status | Published - 1997 |
Keywords
- Adsorption
- C
- Film growth
- Fullerenes
- Metal
- STM
- Semiconductor
ASJC Scopus subject areas
- Condensed Matter Physics
- Metals and Alloys