論文

査読有り
2007年

Ordered arrays of organometallic iridium complexes with long alkyl chains on graphite

CHEMISTRY-A EUROPEAN JOURNAL
  • Joe Otsuki
  • ,
  • Tsubasa Tokimoto
  • ,
  • Yuki Noda
  • ,
  • Tomohiro Yano
  • ,
  • Takeshi Hasegawa
  • ,
  • Xiaoming Chen
  • ,
  • Yoshio Okamoto

13
8
開始ページ
2311
終了ページ
2319
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1002/chem.200600972
出版者・発行元
WILEY-V C H VERLAG GMBH

Iridium(III) fac-tris(2-phenylpyridine) fac-[Ir(ppy)(3)] complexes equipped with long alkyl chains were prepared to examine their capability to form organized arrays on the surface of highly oriented pyrolytic graphite (HOPG). The molecules form lamellar arrays at the 1-phenyloctane/HOPG interface. From the analysis of the STM images, it was concluded that the molecules align with alkyl chains being interdigitated. Similar lamellar arrays were also obtained at the air/HOPG interface upon drop-casting of toluene solutions. The lamellar structure at the molecular level leads to rectangular two-dimensional crystalline domains a few hundred nanometers long (nanoslips). Infrared external reflection spectroscopy suggested that the adsorbed alkyl chains adopt the trans-zig-zag conformation in the nanoslip, although the orientations of the zigzag plane of the alkyl groups are mixed. Cyclic, voltammetry indicates fast electron transfer between the adsorbed molecules and the substrate and significant intermolecular electronic interactions. It was found that annealing at high temperatures is an effective method to prepare ordered assemblies more than a few micrometer scale (microslips). The orientations of the nanoslips prepared from the racemic mixture exhibited an apparent 12-fold symmetry, while its optically active enantiomer resulted in more irregular domains with a six-fold symmetry, implying an important role of chirality on packing at the molecular level and on the orientation of the domains at larger scales. When drop-cast from more concentrated solutions than a few hundreds of micromolar, multilayers were obtained, in which the alkyl chains in the molecules are more or less perpendicular to the surface. This structure can be transformed into the nanoslips upon standing.

リンク情報
DOI
https://doi.org/10.1002/chem.200600972
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000244805500017&DestApp=WOS_CPL
ID情報
  • DOI : 10.1002/chem.200600972
  • ISSN : 0947-6539
  • Web of Science ID : WOS:000244805500017

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