Advanced Materials

Cover image for Advanced Materials

November 1992

Volume 4, Issue 11

Pages fmi–fmi, 714–771

  1. Masthead

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

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041101

  2. Essay

    1. Top of page
    2. Masthead
    3. Essay
    4. Articles
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews
    1. Electronic mail in Europe (pages 714–717)

      Frank Fassbender

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041102

      How can electronic mail improve access to, and the exchange of, scientific information? This is the question addressed. The structure of the various systems, their current status and development, and their importance with respect to participation in, for example, the BRITE-EURAM projects, are discussed. A new European network, Y-NET, which uses the X.400 system, is described and the Network's activities aimed at promoting the use of e-mail services reviewed.

  3. Articles

    1. Top of page
    2. Masthead
    3. Essay
    4. Articles
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews
    1. Spin Transition Molecular Materials for displays and data recording (pages 718–728)

      Prof. Olivier Kahn, Jonas Kröber and Charlotte Jay

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041103

      The development of recording media based on molecular spin-transition (ST) materials is discussed and applications demonstrated for the first time. The figure shows a compound which exhibits an ST and which is based on FeII and 1,2,4-triazole units. The central FeII ion undergoes an ST at around 210 K which is accompanied by a purple-white color change. Requirements for future progress are reviewed.

    2. Diagnostics and modeling of silane and methane Plasma CVD Processes (pages 729–736)

      Dr. Paul B. Davies and Dr. Philip M. Martineau

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041104

      The deposition of hydrogenated amorphous silicon and diamond can be achieved using plasma-enhanced chemical vapor deposition. In order to optimize the deposition process and thus the property profiles of the materials obtained it is important that the gas-phase and surface reactions are understood. The modeling methods and the diagnostic techniques used to follow the processes involved are reviewed and the plasma chemistry of diamond and amorphous silicon deposition compared.

  4. Communications

    1. Top of page
    2. Masthead
    3. Essay
    4. Articles
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews
    1. Synthesis and reduction of 1,4-phenylene-bridged oligoporphyrins (pages 737–739)

      Dirk Hammel, Peler Erk, Barbara Seliuler, Prof. Dr. Jürgen Heinze and Prof. Klaus Müllen

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041105

      The charge-storage capability of oligoporphyrins (for example that shown in the figure) have been investigated. This has been made possible by the development of a straightforward synthesis of aryl-substituted dipyrromethanes.

    2. The synthesis and magnetic behavior of the first mesogenic μ-oxo-bridged iron(III) complex (pages 739–741)

      Dr. Yury Galyametdinov, Dr. Galina Ivanova, Klaus Griesar, Dr. Andrew Prosvirin, Dr. Igor Ovchinnikov and Prof. Wolfgang Haase

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041106

      Metallomesogens are under investigation as potential molecular ferromagnets, ferroelectrics, and second order nonlinear optical materials. Metallomesogens containing FeIII ions are rare but here, the first liquid crystal containing two FeIII ions and teh first complex of FeIII exhibiting a nematic mesophase is reported. The synthesis and magnetic behavior of the μ-oxo-bridged complex of FeIII and Schiff's base are discussed.

    3. Electric-field-induced room-temperature doping in CuInSe2 (pages 741–745)

      Abram Jakubowicz, Geula Dagan, Claus Schmitz and David Cahen

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041107

      The electric-field-induced doping of semiconductors to form permanently-doped, stable device structures using strong electric fields at room temperature is reported. The figure is a secondary electron image of two gold electrodes contacting the surface of the CuInSe2 sample. Electric-field application has resulted in the contact becoming ohmic (superimposed trace) indicating that an internal doping profile has been created.

    4. A new method for thermal polycondensation of volatile molecular precursors—synthesis of polymeric silicon methyldiimide si(NH)NCH3 (pages 746–747)

      Prof. Martin Jonsen and Josua Löffelholz

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041108

      Inorganic polymers are attractive precursors for high-performance ceramics. A new method of producing the polymers via thermal polycondensation of volatile molecular precursors is presented which does not involve the use of catalysts and therefore avoids contamination of the polymers with the catalysts or with byproducts of the catalytic reaction. The example presented is the polycondensation of tetrakis(methylamino)silane, which is a readily available precursor for Si3N4/SiC ceramics.

    5. Synthesis of unsymmetrical biaryls via low-coordination palladium species (pages 747–749)

      Dr. Sophie Gervat, Dr. Eric Léonel, Dr. Jean-Yves Barraud and Dr. Victorin Ratovelomanana

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041109

      The biaryl unit is a fundamental feature of a large number of nonlinear optical materials and liquid crystals. Unsymmetrical biaryls (see figure) have been shown to be of particular interest, exhibiting amongst other things a high electro-optic coefficient. The synthesis of the new unsymmetrical biaryls involves the palladium-complexcatalyzed coupling of an organometallic derivative with an aromatic halide.

    6. Electrochemical deposition and characterization of poly(2,5-dimethoxyaniline): A new highly conducting polyaniline with enhanced solubility, stability and electrochromic properties (pages 749–752)

      Prof. Gianni Zotti, Nicola Comisso, Dr. Giuseppe D'Aprano and Dr. Mario Leclerc

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041110

      Substituted polyanilines are of interest due to their increased solubility over polyaniline. However, early experiments showed that the substituted materials, while exhibiting a higher solubility (and thus workability), were also less conducting. Here, it is shown that dialkoxy substitution of aniline increases solubility of the polymer while not reducing the conductivity. The lower steric hindrance caused by teh methoxy groups in comparison with methyl groups is thought to be responsible.

    7. The Evil Referee (page 752)

      Dr. Richard L. Harlow

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041111

  5. Research News

    1. Top of page
    2. Masthead
    3. Essay
    4. Articles
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews
    1. The Top-CARL, process: A patterning technique for organic materials (pages 753–756)

      Dr. Rainer Leuschner, Hellmut Ahne, Albert Hammerschmidt, Günter Kolodziej, Jens Nordmann, Erwin Schmidt, Michael Sebald and Recai Sezi

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041112

      The patterning of organic layer materials is often hindered by the effects of the conditions used to “develop” the resist material, for example high temperatures for strong bases, which attack the substrate. The process described here allows the patterning even of delicate layers of oriented nonlinear optical polymers. The figure shown a patterned polyimide film 115 μm thick.

    2. Elctroluminescence: A bright future for conjugated polymers? (pages 756–758)

      Dr. Donal D. C. Bradley

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041113

      Conjugated polymer electroluminescence has recently been attracting a great deal of attention. The color range achievable now spans red, gree, and blue, and it has also been shown that polymer-based light-emitting diodes can be formed as flexible structures. Progress made in the synthesis of the polymers, the patterning of thin films of the polymers for application in large-area displays, the improvement of device efficiencies, and teh identification of the charge carriers involved is discussed.

    3. Materials harder than diamond? (pages 759–761)

      Ralf Riedel

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041114

      The hardest known materials, diamond and cubic boron nitride, are thermodynamically stable only at high pressure and temperature. Chemical vapor deposition and sputtering have offered low-pressure alternatives to the traditional synthetic methods and these techniques have recently been exploited for the production of new super-hard materials such as boron carbonitride and carbon nitride, which could be harder than diamond.

    4. Porous silicon preparation: Alchemy or electrochemistry? (pages 762–764)

      Dr. Volker Lehmann

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041115

      In microporous silicon (microPS) every tenth atom is a surface atom and surface processes in silicon are notoriously difficult to study, making the investigation of effects such as electroluminescence difficult. Add to this the profound effects of varying the production parameters and one has a complicated situation where results are often difficult to interpret correctly. Several preparation techniques are reviewed and recent progress made in understanding microPS discussed.

    5. Highly branched polymers (pages 764–766)

      Dr. Young H. Kim

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041116

      Well-defined, large dendritic molecules with branches at almost every repeat unit have recently been shown to form ordered structures such as gels and liquid-crystalline phases. The highly branched Highly Branched Polymers polyamide shown in the Figure forms, for example, a nematic phase as a 40 wt-% solution in amides, and as a 60 wt-% solution forms a gel static conditions but becomes fluid under shear stress.

  6. Materials Forum

    1. Top of page
    2. Masthead
    3. Essay
    4. Articles
    5. Communications
    6. Research News
    7. Materials Forum
    8. Book Reviews
    1. Materials Forum (page 767)

      Article first published online: 15 SEP 2004 | DOI: 10.1002/adma.19920041117

  7. Book Reviews

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

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