Advanced Materials

Cover image for Advanced Materials

December 1993

Volume 5, Issue 12

Pages 878–945

  1. Masthead

    1. Top of page
    2. Masthead
    3. Essay
    4. Reviews
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews
    1. Masthead (page 878)

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051201

  2. Essay

    1. Top of page
    2. Masthead
    3. Essay
    4. Reviews
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews
    1. Intrinsically conducting polymers—quo vadis? (pages 879–886)

      Dr. Peter Bäuerle

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051202

      Of the various types of synthetic metals, intrinsically conducting polymers (once discovered) quickly became te materials most frequently studied, owing to their properties, structural variability, and great potential for commercial applications. This month's essay traces the progress made in their investigation during the last 15 years as reflected in the contributions presented at the series of biennial international conference on synthetic metals (ICSM). Possible directions for their future development are also outlined.

  3. Reviews

    1. Top of page
    2. Masthead
    3. Essay
    4. Reviews
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews
    1. Sensor materials for solvent vapor detection—donor–acceptor and host–guest interactions (pages 887–895)

      Prof. Franz L. Dickert and Dr. Alexander Haunschild

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051203

      Sensors for a huge variety of detection tasks can be made by combining chemically sensitive materials with microstructured physical devices. How individual analyte species can be recognized using host–guest binding schemes (the Figure shows a paracyclophane host molecule) and how categories of compounds can be identified using sensors that respond to different functionalities are reviewed.

    2. Crystal structures of oligothiophenes and their relevance to charge transport (pages 896–908)

      Dr. Shu Hotta and Katsunori Waragai

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051204

      The crystal structures and morphologies of oligothiophenes, in the form of both single crystals and thin films, are reviewed and compared with those of other oligomers and conducting polymers. The “herringbone” structure emerges as a pivotal motif, in particular for charge transport. Although further research is necessary to elucidate the charge transport mechanism, this does not prevent the structural and electronic features of conducting oligomers being exploited in electronic devices such as FETs and LEDs.

  4. Communications

    1. Top of page
    2. Masthead
    3. Essay
    4. Reviews
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews
    1. Side chain influence on mesomorphic properties: Low-temperature melting of metal-containing liquid crystals (pages 909–912)

      Dr. Pascal Maldivi, Dr. Laurence Bonnet, Dr. Anne-Marie Giroud-Godquin, Dr. Mohammed Ibn-Elhaj, Dr. Daniel Guillon and Dr. Antoine Skoulios

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051205

      Metal-containing liquid crystals offer the possibility of obtaining mesogenic materials with novel electronic properties. However, the transition temperatures need to be reduced before applications can be found. The authors describe the first fully characterized metallomesogens with an authentic columnar mesophase near room temperature, which were obtained by inserting carbon-carbon double bonds as the “R” group in te carboxylate ligands (see Figure).

    2. Development of novel biosensor enzyme electrodes: Glucose oxidase multilayer arrays immobilized onto self-assembled monolayers on electrodes (pages 912–915)

      Prof. Itamar Willner, Azalia Riklin, Benjamin Shoham, Dalia Rivenzon and Dr. Eugenii Katz

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051206

      Amperometric biosensors under development are based on electron transfer communication between enzyme redox sites and electrodes. These require well-organized networks of enzymes exhibiting long-range electron transfer properties. An enzyme electrode is described that consists of glucose oxidase networks organized on a self-assembled monolayer of functionalized thiols on gold electrodes. The protein array supports electrical communication with the electrode, and the resulting assembly can be used as a glucose biosensor.

    3. Magnetic properties of polyoxovanadates: Magnetic confirmation of the valence state of the vanadium centers in Na6[H6 V12O30F2] · 22H2O (pages 915–917)

      Prof. Achim Müller, Ralf Rohlfing, Dr. Anne-Laure Barra and Prof. Dante Gatteschi

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051207

      Oxovanadium clusters are intersting both as moels of bulk magnets and in their own right. Results are presented suggesting that in Na6[H6V12O30F2]·22H2O (see Figure) it is meaningful to decide which particular vanadium centers should be considered at 5⊕ and which as 4⊕. It is shown that in principle ist is possible to tune and design the topology, and thus the magnetic properties, of polyoxovanadates(IV/V) by means of the template effect.

    4. Highly oriented poly(di-n-alkylsilylene) films on oriented PTFE substrates (pages 917–919)

      Dr. Holger Frey, Dr. Sergej Sheiko, Prof. Martin Möller, Prof. Jean Claude Wittmann and Prof. Bernard Lot

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051208

      Highly oriented polysilylene layers have potential applications in electrophotography, nonlinear optics, display fabrication, and microlithography. The preparation of such layers by crystallization on a highly oriented PTFE substrate is reported, and their assessment by optical birefringence, electron diffraction and dichroic infrared experiments described. Why this orientation technique works is not yet clear, especially as it can be applied to poly(di-n-alkylsilylen)s with different crystal structures. Several possible underlying mechanisms are discussed.

    5. Ultrathin films of cellulose on silicon wafers (pages 919–922)

      Dr. Matthias Schaub, Dr. Gerhard Wenz, Prof. Gerhard Wegner, Dr. Andreas Stein and Prof. Dieter Klemm

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051209

      The first preparation of thin films of cellulose itself is reported. Cellulose exhibits excellent wetting behavior, is extremely stable against oxidation and other chemical degradation and in thin-film form would have a number of applications. The method involves the preparation of LB films of trimethylcellulose (see Figure) and the in situ conversion of these thin films on silicon substrates to cellulose.

    6. Electroluminescence from oligothiophene-based light-emitting devices (pages 922–925)

      Friedhelm Geiger, Marion Stoldt, Dr. Heinz Schweizer, Dr. Peter Bäuerle and Prof. Eberhard Umbach

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051210

      The first LEDs based on oligothiophenes are reported. Polymer-based devices have the advantages that their physical properties can be tailored, they can be easily fabricated, and they can emit all colors, but they have poor stability, a high impurity level, and low luminance. The systematic study of the electroluminescence properties of oligothiophenes described here is aimed to isolate the effects of various parameters, by controlling the structure of the oligomers used, and to extrapolate the results to polymers for use in LEDs.

    7. Highly ordered films of neat calix[4]arenes for second order nonlinear optics (pages 925–930)

      Dr. Erik Kelderman, Gerard J. T. Heesink, Dr. Lode Derhaeg, Dr. Thierry Verbiest, Dr. Piet T. A. Klaase, Dr. Willem Verboom, Dr. Johan F. J. Engbersen, Dr. Niek F. van Hulst, Dr. Koen Clays, Prof. Andre Persoons and Prof. David N. Reinhoudt

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051211

      In substituted calix[4]-arenes—cyclophanes consisting of four phenol moieties connected by methylene bridges[BOND]the number and also the relative positions of the donor and/or acceptor π-conjugated (D-π-A) units can be varied by changing the configuration. The Figure illustrates the cone configuration. The molecular and thin-film NLO properties of three tetra-D-π-A-substituted calix[4]arenes, including their orientation in thin films and the stability of their NLO properties, are described.

    8. Low power nonlinear optical response of C60 and C70 fullerene solutions (pages 930–934)

      Dr. Fryad Z. Henari, Shane MacNamara, Orla Stevenson, Joseph Callaghan, Declan Weldon and Prof. Werner J. Blau

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051212

      Solutions of C60 and C70 exhibit a large third-order nonlinear response, even when investigated with low-power visible lasers. The remarkably large nonlinearity observed is attributed to a combined effect of thermally induced nonlinear refractive index changes and simultaneous nonlinear absorption. Fullerenes have the potential for applications in all-optical devices if they retain the same properties as in solution when dispersed in a transparent polymer matrix.

  5. Research News

    1. Top of page
    2. Masthead
    3. Essay
    4. Reviews
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews
    1. Scanning probe surface modification (pages 935–938)

      Thomas S. Corbitt, Prof. Richard M. Crooks, Claudia B. Ross, Prof. Mark J. Hampden-Smith and Jonathan K. Schoer

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051213

      Nanometer-scale manipulation of surfaces by scanning probe devices has expanded amazingly since the first reports in the mid-1980s. General approaches to scanning probe microscope induced surface patterning are discussed. The Figure shows a scanning electron micrograph of an STM-defined pattern of a HS(CH2)17CH3 monolayer resist on a Au(111) substrate.

    2. Functionalized viologens for novel electron relay systems (pages 938–940)

      Dr. Atsushi Kameyama, Dr. Yoko Nambu and Dr. Takeshi Endo

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051214

      Molecular electron relay systems based on viologens substituted with, for example, crown ethers offer the opportunity to combine molecular recognition/complexation with electron transfer. Recent progress in the synthesis of such materials is reported, together with examples of their application as electron-transfer mediators in biomimetic electron transfer systems, and the controlled reduction of organic compounds such as aromatic aldehydes and α-ketoesters in organic solvents in which the reducing agent (e.g. Na2S2O4) is usually insoluble.

  6. Materials Forum

    1. Top of page
    2. Masthead
    3. Essay
    4. Reviews
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews
    1. Materials Forum (page 941)

      Article first published online: 29 OCT 2004 | DOI: 10.1002/adma.19930051215

  7. Book Reviews

    1. Top of page
    2. Masthead
    3. Essay
    4. Reviews
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews

SEARCH

SEARCH BY CITATION