C O M M U N I C A T I O N S
optical microscopy and the isotropic small-angle reflection implied
columnar structures for 1b which are, however, established only
over short-range, whereby 1a and 1c exhibited self-assembly over
long-range.
In conclusion, we have developed a synthetic protocol yielding
2
the novel D symmetric zigzag nanographenes, and allowing a
specific substitution of the ovalene corona. The latter appeared as
a key feature to modify the intracolumnar arrangement in a facile
way. It thus became possible to modify the supramolecular
organization of an extended PAH from helical to a unique staggered
superstructure. It is expected that the variation of the molecular
packing for one system is accompanied by a different performance
in electronic devices.12
Acknowledgment. The authors acknowledge financial support
from the Deutsche Forschungsgemeinschaft (Schwerpunktpro-
gramm: Organische Feldeffekt-Transistoren) and the EU project
NAIMO (Integrated Project Number NMP4-CT-2004-500355).
1
Supporting Information Available: Experimental procedures, H
NMR, UV-vis, and photoluminescence spectra, POM, thermal behav-
ior, and indexed 2D-WAXS patterns. This material is available free of
charge via the Internet at http://pubs.acs.org.
Figure 1. Two-dimensional WAXS patterns of (a) 1a (arrows indicate
intracolumnar periods of 1 nm), (b) 1b, (c) 1c (Miller’s indices for the
intracolumnar stacking and the higher order reflections are indicated), and
(d) illustration of the rotation assigned for 1c.
References
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3
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(
(
(
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i
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i
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