C O M M U N I C A T I O N S
were seen in Figure 4a,b. They must be the aggregates of the linear
polymers. The fibers formed on the mica plate have widths of 60-
90 nm and heights of 1.2-1.9 nm (Figure 4c). Judging from the
calculated structure of the oligomers (Figure S3), the alkyl side
chains have length of about 3.5 nm, which is longer than the
observed height. This suggests that the alkyl chains adopt parallel
arrangement to the mica surface, and the nano assemblies are
probably composed of a bundle of 40-60 polymer chains created
by entangling the alkyl side chains with van der Waals interaction
(Figure S4).
In summary, we succeeded showing the polymeric nano network
by the fullerene-calix[5]arene interaction. At a low concentration,
the supramolecular complexes mainly adopt the trimeric nature;
however, the polymeric nature appeared in solid phase. The fibrous
assemblies created the supramolecular nano network. The detailed
studies are underway.
Figure 2. UV/vis absorption spectra of 1 (2.5 × 10-5 mol/L) and 2 (2.5
× 10-5 mol/L) in CHCl2CHCl2 at (a) 298, (b) 318, (c) 338, (d) 348, and
(e) 368 K.
Acknowledgment. We are grateful to Prof. Y. Tanimoto and
Prof. Y. Fujiwara for their kind help and fruitful discussions on
AFM measurements.
Supporting Information Available: Synthetic procedures of
compounds 1 and 2, 1H NMR spectra of the mixtures, Stejskal-Tanner
plots of 2 and 1‚2, and the calculated structure of the oligomer. This
Figure 3. Scanning electron micrograph of the cast-film of the mixture of
1 and 2 on a glass plate.
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