J. Phys. IV France 114 (2004) 667
Development of TTF-based self-assembled monolayer systems and their electronic propertiesT. Enoki1, 1, Y. Yokota1, R. Yuge1, W. Tu1, A. Miyazaki1, K. Takai1 and K. Fukui1
1 Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo 152-8551, Japan
Self-assembled monolayer (SAM) systems of alkanethiol and TTF-substituted alkanethiol molecules on Au substrate and metal nanoparticles are investigated. TTF-substituted alkanethiol molecules form charge transfer complex SAM with TCNQ molecules, where charge transfer (CT) rate becomes similar to that in bulk TTF TCNQ crystal. TTF-substituted alkanethiol SAMs with long alkyl chains shows Coulomb-blockade-type electron transport owing to the resistance of the long alkyl chain bridge. In Pt nanoparticles with alkanethiol SAMs on their surface, CT takes place from core Pt nanoparticle to surface SAMs, producing an electron deficient state in Pt core nanoparticle. Pd nanoparticles with SAMs of mixtures of alkanethiol and TTF-substituted alkanethiol molecules take a large reduction of the Pauli paramagnetic susceptibility, which is brought about by CT. Key words. Nanoparticle - self-assembled monolayer - interface - quantum size effect - TTF donor - charge transfer.
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