Fig. 3 STM image of 3b self-assembly on HOPG from 1,2,4-trichlorobenzene in constant current mode using a Pt/Ir tip. (a) Large scan area with step
˚
˚
edges and grain boundaries: Iset 5 26.9 pA, Vset 5 2564 mV, scale bar is 10 nm. (b) Lamellar structure with periodicities of 33 A (lamellae) and 15 A
(substructure in each lamella), respectively: Iset 5 95.5 pA, Vset 5 21.00 V. (c) A CPK model of 3b superimposed onto the STM image, alkyl chains are
omitted for clarity, same conditions as (b), scale bar is 1 nm.
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We thank N. Tang for assistance in the synthesis of 2,7-
diamino-1,8-naphthyridine, L. Zhang, S. Bohle and F. Be´langer
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NSERC, FQRNT, CFI, Concordia University and the German
Science Foundation (‘‘Deutsche Forschungsgemeinschaft’’) within
the Research Center 569 (‘‘Sonderforschungsbereich 569’’) for the
generous support of this work. We also acknowledge our
membership in the FQRNT-supported, multi-university Centre
for Self-Assembled Chemical Structures (CSACS). This manu-
script is dedicated to the memory of Dr Bernard Dietrich.
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Notes and references
§ CCDC 267802 (2), 267803 (3c) and 267804 (4). For crystallographic data
in CIF or other electronic format see DOI: 10.1039/b510118b
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This journal is ß The Royal Society of Chemistry 2005
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