@article{SchulzBrumaBrehmer1997,
  author    = {Schulz, Burkhard and Bruma, Maria and Brehmer, Ludwig},
  title     = {Aromatic poly(1,3,4-oxadiazole)s as advanced materials},
  year      = {1997},
  abstract  = {Poly(1,3,4-oxadiazole)s have been the focus of considerable interest with regard to the- production of high- performance materials, particularly owing to their high thermal stability in oxidative atmosphere and specific properties determined by the structure of 1,3,4-oxadiazole ring, which, from the spectral and electronic points of view, is similar to a p-phenylene structure.[1] Besides their excellent resistance to high temperature, polyoxadiazoles have many desirable characteristics, such as good hydrolytic stability, high glass transition temperatures, low dielectric constants, and tough mechanical properties. Some polyoxadiazoles have semiconductive properties, other structures can be electrochemically doped and thus made conductive, and other have liquid-crystalline properties, which make them very attractive for a wide range of high-performance applications. They exhibit excellent fiber- and film-forming capabilities, thus being considered for use as heat-resistant reinforcing fibers for advanced composite materials, highly resistant fabrics for the filtration of hot gases, special membranes for gas separation or reverse osmosis, precursors for highly oriented graphite fibers, films, and blocks to be used in the construction of electronic instruments based on X-rays, neutron beams, or a-particles, or in the construction of nuclear reactor walls. Since they were first reported in 1961,[2] a wide variety of polymers containing 1,3,4-oxadiazole rings have been synthesized, and their preparation, characterization, and physico-mechanical properties have been periodically reviewed .[3-8] This article will present a general overview of this class of polymers and will refer to the work carried out by different researchers in the last ten years with the emphasis on the potential uses of such polymers as advanced materials.},
  language  = {en}
}
@article{SchulzStillerZetzscheetal.1997,
  author    = {Schulz, Burkhard and Stiller, Burkhard and Zetzsche, Thomas and Knochenhauer, Gerald and Brehmer, Ludwig},
  title     = {Characterization of crystals based on 1,3,4-oxadiazoles by atomic force microscopy},
  year      = {1997},
  abstract  = {The surface structures of crystals based on aromatic oxadiazoles were investigated by AFM. The crystal structure for 2,5-di(p-tolyl)-1,3,4-oxadiazole (DTO) differs from that of 2,5-di (4-methoxycarbonyl-phenyl)-1,3,4- oxadiazole (DMPO). In DMPO all molecules show parallel orientation to the surface in such a way that the surface is formed as well as by the nitrogen atoms of the heterocyclic rings and the methyl groups of the ester substituents. By contrast, the oxadiazole molecules in DTO crystals are oriented perpendicular to the crystal surface. The experimental data are interpreted by molecular modelling. It is shown that there is a difference between molecular structure of the surface, as detected by AFM, and the bulk structure determined by X-ray diffraction.},
  language  = {en}
}
@article{KnoblochPenacoradaBrehmer1997,
  author    = {Knobloch, Harald and Pe{\~n}acorada, Florencio and Brehmer, Ludwig},
  title     = {Ellipsometric studies on Uranyl Arachidate Langmuir-Blodgett films},
  year      = {1997},
  language  = {en}
}
@article{JanietzKatholyDietzeletal.1997,
  author    = {Janietz, Dietmar and Katholy, Stefan and Dietzel, Birgit and Brehmer, Ludwig},
  title     = {Monolayer behaviour of two-fold hydroxy terminated sheet-like Tetrakis(phenylethynyl) benzene derivatives},
  year      = {1997},
  language  = {en}
}
@article{SchroeterPlehnerTschierskeetal.1997,
  author    = {Schr{\"o}ter, J. A. and Plehner, R. and Tschierske, C. and Katholy, Stefan and Janietz, Dietmar and Pe{\~n}acorada, Florencio and Brehmer, Ludwig},
  title     = {Monolayer properties of a new family of amphiphiles with an unusual head-group topology},
  year      = {1997},
  language  = {en}
}
@article{ReichePenacoradaGeueetal.1997,
  author    = {Reiche, J{\"u}rgen and Penacorada, Florencio and Geue, Thomas and Pietsch, Ullrich and Brehmer, Ludwig},
  title     = {Monolayers and multilayers of uranyl arachidate : in-plane structure of uranyl arachidate multilayers},
  year      = {1997},
  abstract  = {The molecular in-plane structure of uranyl arachidate Langmuir-Blodgett (LB) films formed at different subphase pH values was analysed by means of X-ray grazing-incidence diffraction. For multilayers formed at low subphase pH a reorganisation of the arachidic acid film structure is confirmed. At appropriate subphase pH values, reorganisation of the film structure, e.g. via the formation of three-dimensional crystallites, is prevented by the presence of the uranyl ions and by the subsequent introduction of conformational disorder (gauche defects) in the alkyl chains. The observation of a macroscopic flow-induced in-plane texture in these uranyl arachidate LB films has profound implications for the design of ordered, supramolecular structures by the Langmuir-Blodgett technique.},
  language  = {en}
}
@article{SchulzKaminorzBrehmer1997,
  author    = {Schulz, Burkhard and Kaminorz, Yvette and Brehmer, Ludwig},
  title     = {New aromatic poly(1,3,4-oxadiazole)s for light emitting diodes},
  year      = {1997},
  abstract  = {New aromatic poly(1,3,4-oxadiazole)s were synthesized having excellent film forming properties due to their solubility in common organic solvents. The investigated new polyoxadiazoles can be used as emission material in single layer LED. The poly- oxadiazoles show an emission in the range of blue to yellow light. The external quantum efficiency as well as the turn-on voltage of the devices are influenced when blends of the polyoxadiazole with hole transport materials are used.},
  language  = {en}
}
@article{ReicheZetzscheHelmsetal.1997,
  author    = {Reiche, J{\"u}rgen and Zetzsche, Thomas and Helms, Andreas and Freydank, Anke-Christine and Knochenhauer, Gerald and Schulz, Burkhard and Brehmer, Ludwig},
  title     = {Organized molecular films of oxadiazole compounds formed by vacuum deposition},
  year      = {1997},
  language  = {en}
}
@article{PenacoradaReicheZetzscheetal.1997,
  author    = {Penacorada, Florencio and Reiche, J{\"u}rgen and Zetzsche, Thomas and Dietel, Reinhard and Brehmer, Ludwig and Saja, Jose-Antonio de},
  title     = {Stabilisation of fatty acid mono- and multilayers by simultaneous polyelectrolyte complexation and salt formation with cadmium ions},
  year      = {1997},
  abstract  = {The complexation of highly ordered fatty acid monolayers with polyelectrolytes is expected to yield well- ordered Langmuir films suitable for the formation of Langmuir-Blodgett multilayers with improved long-term stability. Studies of the surface pressure-area isotherms and of the surface potential kinetics yield detailed information regarding the influence of these polymeric counterions on the monolayer properties. The injection of bivalent metal salts into the subphase after the complexation was used to improve the order and stability of the mono- and multilayers. The corresponding Langmuir-Blodgett films were investigated by means of X-ray reflectivity measurements and scanning force microscopy. The polyion complex multilayers show a strongly increased mechanical stability compared with films of fatty acid salts formed with bivalent metal ions. These structures are expected to be suitable as ultrathin separation layer for gas separation or ultrafiltration membranes.},
  language  = {en}
}
@article{PapraPenacoradaReicheetal.1997,
  author    = {Papra, Alex and Penacorada, Florencio and Reiche, J{\"u}rgen and Katholy, Stefan and Brehmer, Ludwig and Hicke, Hans-Georg},
  title     = {Structure and Stability of Langmuir Monolayers and Langmuir-Blodgett Films of Bisaroyl Azide Bolaamphiphiles},
  year      = {1997},
  abstract  = {Langmuir-Blodgett films of bolaamphiphiles with reactive head groups can be used for the surface modification of composite membranes for gas separation processes. The scope of our investigations was to get a detailed insight in the monolayer behaviour and LB film structure of previously synthesized bisaroyl azide bolaamphiphiles. The layers have been analyses by means of surface potential measurements and Brewster angle microscopy. Furthermore parameters for a successful LB Film deposition were found. As expected for a molecule with two hydrophilic ends the transfer ratio on upstroke was close to one and on downstroke no transfer occurred. The multilayer structure was analysed by scanning force microscopy and X-ray reflectivity measurements. The SFM images revealed a periodic in plane structure on molecular level. Based on a combination of the X-ray data with results of other methods two possible models of the multilayer structure are presented},
  language  = {en}
}
@article{ReicheKnochenhauerDieteletal.1997,
  author    = {Reiche, J{\"u}rgen and Knochenhauer, Gerald and Dietel, Reinhard and Freydank, Anke-Christine and Zetzsche, Thomas and Pietsch, Ullrich and Brehmer, Ludwig and Barberka, Thomas Andreas and Geue, Thomas},
  title     = {Structure of thermally treated oxadiazoleamide Langmuir-Blodgett films},
  year      = {1997},
  abstract  = {The thermal treatment of Y-type Langmuir-Blodgett (LB) films formed from the amphiphilic derivative of 2,5- diphenyl-1,3,4-oxadiazole 1 results in changes of the molecular packing. These changes have been analysed by a combination of X-ray specular reflectivity data, X-ray grazing incidence diffraction data and scanning force microscopy images, On the basis of these experimental data we have simulated possible supramolecular structures, These simulations provide insight into the intermolecular interactions giving rise to the observed structural transitions. The crystalline structure induced by thermal treatment of the LB films is characterized by a uniaxial texture, which is correlated with the dipping direction during deposition of the LB film.},
  language  = {en}
}
@article{ReicheSchulzKnochenhaueretal.1997,
  author    = {Reiche, J{\"u}rgen and Schulz, Burkhard and Knochenhauer, Gerald and Dietzel, Birgit and Freydank, Anke-Christine and Zetzsche, Thomas and Brehmer, Ludwig},
  title     = {Supramolecular structures formed from heterocyclic aromatic molecules},
  year      = {1997},
  abstract  = {This paper describes the formation and structure investigation of Langmuir monolayers and Langmuir-Blodgett multilayers formed from amphiphilic derivatives of 2,5-diphenyl-1,3,4-oxadiazole. The 2,5-diphenyl-1,3,4-oxadiazole group as a functional unit with interesting physical and chemical properties is maintained, while the head group, the length of the alkyl chain and the structure of the coupling unit between aromatic and aliphatic part of these linear short-chain amphiphiles is systematically varied in order to explore the influence of this change on the film forming properties and the stability of Langmuir and Langmuir-Blodgett films. Molecular mechanics simulations are shown by these systematic variations to be suitable for the prediction of optimal chemical structures allowing for a stable stratified molecular packing. The combination of a detailed structure investigation of the multilayers based on scanning force microscopy and X-ray data with molecular mechanics simulations yields an insight into the packing of the molecules and the intermolecular interactions.},
  language  = {en}
}
@article{MetzgerChenHoepfneretal.1997,
  author    = {Metzger, Robert M. and Chen, Bo and H{\"o}pfner, Ulf and Lakshmikantham, M. V. and Vuillaume, Dominique and Kawai, Tsuyoshi and Wu, Xiangli and Tachibana, Hiroaki and Hughes, Terry and Sakurai, Hiromi and Baldwin, Jeffrey W. and Hosch, Christina and Cava, Michael P. and Brehmer, Ludwig and Ashwell, Geoffrey J.},
  title     = {Unimolecular electrical rectification in Hexadecylquinolinium Tricyanoquinodimethanide},
  year      = {1997},
  language  = {en}
}
@article{Brehmer1997,
  author    = {Brehmer, Ludwig},
  title     = {WEH Ferienkurs "Komplexe organisierte Grenz- und Oberfl{\"a}che"},
  year      = {1997},
  language  = {de}
}