Covalently tethering porphyrin-based molecules to an otherwise inert gold substrate allows them to be imaged in an ambient environment using scanning tunneling microscopy. Interpretation of the data is aided by comparing images of mono- and diporphyrin molecules taken with the same tip. At low coverage we obtain a markedly larger average particle size (396 Å2) for diporphyrins than for monoporphyrins (121 Å2). The particle size distributions are very broad, but the images show a characteristic variation of contrast with tip bias, suggesting that the heterogeneity is due to different molecular conformations rather than contamination. We find evidence of ordered structures at high coverage.
|Original language||English (US)|
|Number of pages||4|
|State||Published - Mar 1 1992|
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Surfaces and Interfaces