TY - JOUR A1 - Wüstneck, Rainer A1 - Prescher, Dietrich A1 - Katholy, Stefan A1 - Knochenhauer, Gerald A1 - Brehmer, Ludwig T1 - Surface dilatational rheological study of the trans-cis isomerisation of copolymers with trifluoromethoxy substituted metacrylate monolayers Y1 - 2000 SN - 0927-7757 ER - TY - JOUR A1 - Schulz, Burkhard A1 - Stiller, Burkhard A1 - Zetzsche, Thomas A1 - Knochenhauer, Gerald A1 - Dietel, Reinhard A1 - Brehmer, Ludwig T1 - Characterization of 2,5-di(p-tolyl-1,3,4- oxadiazole) crystals by IR-spectroscopy and atomic force microscopy Y1 - 1995 ER - TY - JOUR A1 - Schulz, Burkhard A1 - Stiller, Burkhard A1 - Zetzsche, Thomas A1 - Knochenhauer, Gerald A1 - Dietel, Reinhard A1 - Brehmer, Ludwig T1 - Crystal structure of 2,5-Di(4- methoxycarbonyl-phenyl)-1,3,4-oxadiazole characterized by AFM and IR- spectroscopy Y1 - 1994 ER - TY - JOUR A1 - Schulz, Burkhard A1 - Stiller, Burkhard A1 - Zetzsche, Thomas A1 - Knochenhauer, Gerald A1 - Brehmer, Ludwig T1 - Characterization of crystals based on 1,3,4-oxadiazoles by atomic force microscopy N2 - 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. Y1 - 1997 ER - TY - JOUR A1 - Schulz, Burkhard A1 - Knochenhauer, Gerald A1 - Brehmer, Ludwig A1 - Janietz, Silvia T1 - Stuctures and properties of aromatic poly(1,3,4-oxadiazole)s Y1 - 1995 ER - TY - JOUR A1 - Schulz, Burkhard A1 - Knochenhauer, Gerald A1 - Brehmer, Ludwig A1 - Janietz, Silvia T1 - Stuctures and properties of aromatic poly(1,3,4-oxadiazole)s Y1 - 1994 ER - TY - JOUR A1 - Schulz, Burkhard A1 - Brehmer, Ludwig A1 - Knochenhauer, Gerald T1 - Supramolecular structures of aromatic 1,3,4-oxadiazole solids Y1 - 1995 ER - TY - JOUR A1 - Reiche, Jürgen A1 - Zetzsche, Thomas A1 - Helms, Andreas A1 - Freydank, Anke-Christine A1 - Knochenhauer, Gerald A1 - Schulz, Burkhard A1 - Brehmer, Ludwig T1 - Organized molecular films of oxadiazole compounds formed by vacuum deposition Y1 - 1997 ER - TY - JOUR A1 - Reiche, Jürgen A1 - Schulz, Burkhard A1 - Knochenhauer, Gerald A1 - Dietzel, Birgit A1 - Freydank, Anke-Christine A1 - Zetzsche, Thomas A1 - Brehmer, Ludwig T1 - Supramolecular structures formed from heterocyclic aromatic molecules N2 - 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. Y1 - 1997 ER - TY - JOUR A1 - Reiche, Jürgen A1 - Knochenhauer, Gerald A1 - Dietel, Reinhard A1 - Freydank, Anke-Christine A1 - Zetzsche, Thomas A1 - Pietsch, Ullrich A1 - Brehmer, Ludwig A1 - Barberka, Thomas Andreas A1 - Geue, Thomas T1 - Structure of thermally treated oxadiazoleamide Langmuir-Blodgett films N2 - 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. Y1 - 1997 ER -