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The magnetic fields in substituted hexabenzocoronenes (HBC) are effective for producing oriented films of discotic liquid-crystalline materials, which allows the investigation of structure-property relationships in magnetically aligned films formed in field-effect transistor structures in a noninvasive, contact-free way. Since the magnetic field alignment is applicable to a wide range of self-assembled systems, this approach can be used for optimizing the properties of functional materials.

Author(s): Natalie Stutzmann [1]; Theo A. Tervoort (corresponding author) [1]; Kees Bastiaansen [1, 2]; Paul Smith (corresponding author) [1] The ability to micropattern materials is of great importance for manufacturing [...]

The chemical structures designed by inserting decoupling spacers between a trisfunctionalized benzene core and the three azobenzene moieties, as well as adding polar end groups to the latter that allow formation of both an amorphous and a liquid-crystalline phase. The obtained nonpolymeric, azobenzene-containing compounds could find valuable application for fabrication of stable holographic volume gratings.

Atomic force microscopy reveals that control of thin film morphology by respective self-assembly of p-type oligo(p-phenylenevinylene)s (OPV)s and n-type perylenebisimides (PBI)s in solution prior to processing results in film architectures which constitute uniform rodlike domains. Such films show improved charge-carrier mobility when compared to films processed from molecular dissolved molecules, and ampipolar field-effect transistors constructed from dyad complexes of OPVs and PBIs exhibit independent pathways for charge transport.

An efficient synthetic route to the first high molecular weight poly(3-hexylthiophene)-Polyethylene (P3HT-PE) block copolymer using ruthenium-catalyzed ring-opening metathesis polymerization (ROMP) is described. The novel P3Ht-PE block copolymers would allow exploration of new functional morphologies and expand the processing and structural toolbox for conjugated materials.

A surface X-ray diffraction study is presented showing that highly ordered and uniaxially aligned hexa(3,7-dimethyl-octanyl)hexa-peri-hexabenzocoronene (HBC-C8,2) films can be fabricated by crystalization from solution onto friction-transferred poly(tetrafluoroethylene) (PTFE) layers. A quasi-2D epitaxial growth mechanism with a grapho-epitaxial component for one of the three phases explains the formation of the three rotational HBC-C8, 2 variants.

Reports on the generation of patterned ceramic surfaces with a feature resolution in the micrometer range by casting aqueous suspensions of high solids loadings onto nonporous polymer molds. Fabrication of high-quality line patterns for alumina, zirconia, cerium gadolinium oxide and tin oxide powders.

The article reports on a simple, rapid film-deposition technique that allows deposited molecules to self-organize into complex architectures with high charge-carrier mobilities where required within a low-charge-carrier-mobility surround that provides electrical insulation for individual devices. It describes the key features and advantages of organic field-effect transistors.