Adsorption and organisation of para-hexaphenyl molecules on Si(100)

• Published in: Applied physics. A, Materials science & processing Vol. 94; no. 4; pp. 767 - 773
• Main Authors: Cranney, M., Chalopin, Y., Mayne, A. J., Dujardin, G.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-03-2009; Springer
• Subjects: Adsorption; Characterization and Evaluation of Materials; Chemisorption; Condensed Matter Physics; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Machines; Manufacturing; Nanocomposites; Nanomaterials; Nanostructure; Nanotechnology; Optical and Electronic Materials; Physics; Physics and Astronomy; Processes; Scanning tunneling microscopy; Solid surfaces and solid-solid interfaces; Spatial distribution; Surface chemistry; Surface structure and topography; Surfaces and Interfaces; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin Films; 42.70.-a; 68.37.Ef; 81.07.Nb; Chemisorption; Scanning tunneling microscopy; Statistical analysis; Molecular orientation; Spatial distribution; Adsorption; Adsorption structure; Silicon
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-008-4976-2

Para-hexaphenyl molecules (p-6P: C
36
H
26
) can be grown as nanofibres on various surfaces having optical properties of technological relevance. We report here the first observations of the initial stages of adsorption of individual p-6P molecules on Si(100)-(2×1) using room temperature Scanning Tunnelling Microscopy (STM). Depending on the substrate temperature, the hexaphenyl molecules adsorb in two configurations; indicating both weak and strong chemisorption. All six phenyl rings are clearly visible and the molecules are found to adsorb with characteristic angles between the long axis of the molecule and the silicon dimer rows. A statistical analysis of the spatial distribution of the molecules suggests that the clustering required for crystallographic nanofibre growth does not occur at the atomic scale under the experimental conditions used here.