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The generation of multifunctional materials by self-assembly of specifically designed molecules, through supramolecular chemistry approaches, currently gathers a great interest in nanotechnology.[1] Cavitands are versatile molecular building blocks for host-guest assemblies.[2] We describe here the design, crystal structure determination and self-assembly in solution and on surfaces of supramolecular polymers from cavitand based compounds. Studies in solution proved evidence for the formation of polymers from specifically designed cavitands, and the aggregation behavior was quantified. The successful translation of the given self-assembly procedure from solution to surfaces required a comprehensive understanding and control over various boundary conditions. Scanning Force Microscopy experiments allowed us to follow such investigation path on different substrates such as mica, graphite and SiOx surfaces, for single as well as double-caged cavitand compounds. The self-assembly behavior has been investigated employing solvents of different polarity and chemically modifying the substrate surface. Rod-like architectures have been in this way visualized on surface. A bending in two dimensions of the single rods has also been observed and it has been correlated to the degree of curvature of the polymer as obtained form simulation studies.
[1] J. M. Lehn, Science 2002, 295, 2400
[2] (a) R. Pinalli, M. Suman, E. Dalcanale, European Journal of Organic Chemistry 2004, 451; (b) L. Pirondini, A.G. Stendardo, S. Geremia, M. Campagnolo, P. Samorì, J.P. Rabe, R. Fokkens, E. Dalcanale, Angew. Chem. Int. Ed. Engl. 2003, 42, 1384.
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