TY - JOUR A1 - Tsukruk, V. V. A1 - Janietz, Dietmar T1 - Evolution of interdigitated molecular packing of discotic liquid crystals across interface Y1 - 1995 ER - TY - JOUR A1 - Stracke, A. A1 - Wendhorff, Joachim Heinz A1 - Goldmann, Daniela A1 - Janietz, Dietmar A1 - Stiller, Burkhard T1 - Gain effects in optical storage : thermal induction of a surface relief grating in a smectic liquid crystal Y1 - 2000 ER - TY - JOUR A1 - Schröter, J. A. A1 - Plehner, R. A1 - Tschierske, C. A1 - Katholy, Stefan A1 - Janietz, Dietmar A1 - Peñacorada, Florencio A1 - Brehmer, Ludwig T1 - Monolayer properties of a new family of amphiphiles with an unusual head-group topology Y1 - 1997 ER - TY - JOUR A1 - Reiche, Jürgen A1 - Janietz, Dietmar A1 - Barberka, Thomas Andreas A1 - Hofmann, Dieter A1 - Brehmer, Ludwig T1 - Comprehensive structure investigation of Langmuir-Blodgett films of disc-shaped molecules N2 - The structure of mono- and multilayers of amphiphilic disc-shaped pentaynes wa inbestigated by Brewsterangle microscopy, X-ray specular reflection and grazing incidence diffraction (GID). X-ray specular reflection experiments confirm the "edge on" arrangement of the molecular discs. The molecular modelling of the Langmuir-Blodgett (LB)- multilayers predicts a columnar in-plane packing of the molecules. A GID experiment with monochromatic synchrotron radiation was used to verify the predicted multilayer structure on molecular level, while the Brewsterangle microscopy gave a deeper insight in the monolayer in-plane structure on micron scale. Y1 - 1995 ER - TY - JOUR A1 - Reiche, Jürgen A1 - Dietel, Reinhard A1 - Lemmetyinen, Helge A1 - Janietz, Dietmar A1 - Lemmetyinen, Helge A1 - Brehmer, Ludwig T1 - Edge-on Langmuir-Blodgett multilayers derived from disc-shaped multiyne mesogens N2 - Langmuir-Blodgett(LB) multilayers were prepared from disc-shaped multiyne mesogens based on amphiphilic alkyl pentakis(aryl-ethynyl)benzene ethers. The two compounds used are characterized by five hydrophobic flexible chains and one hydrophilic substituent at the terminal position of the alkoxy chain. The LB films were analysed by X-ray scattering and spectroscopic measurements. An edge-on arrangement of the two discotic pentaalkynes within Y-type bilayers with a different packing density proved to be possible for the LB films of both compounds. Y1 - 1992 ER - TY - JOUR A1 - Reiche, Jürgen A1 - Barberka, Thomas Andreas A1 - Janietz, Dietmar A1 - Hofmann, Dieter A1 - Pietsch, Ullrich A1 - Brehmer, Ludwig T1 - X-ray structure investigation and computer modelling of Langmuir-Blodgett films formed from disc-shaped pentaalkines Y1 - 1994 ER - TY - JOUR A1 - Marguet, S. A1 - Markovitsi, D. A1 - Goldmann, Daniela A1 - Janietz, Dietmar A1 - Praefcke, K. A1 - Singer, D. T1 - Spectroscopic properties of nematic discotic phenylethynylbenzene derivatives Y1 - 1997 ER - TY - JOUR A1 - Marguet, S. A1 - Markovitsi, D. A1 - Germain, A. A1 - Millie, P. A1 - Daute, D. A1 - Janietz, Dietmar T1 - Experimental and theoretical study of the photophysical properties of multichromophoric molecules : the phenylethynylbenzene derivatives, light on organized molecular systems Y1 - 1995 ER - TY - JOUR A1 - Jutila, Arimati A1 - Janietz, Dietmar A1 - Reiche, Jürgen A1 - Lemmetyinen, Helge T1 - Photophysical investigation of Langmuir-Blodgett films of amphiphilic discotic penta-alkynes N2 - Amphiphilic discotic pentakis (arylethynyl) benzene compounds 1 and 2 containing an enlarged aromatic core functioning as a chromophoric p-electron system were studied with regard to their photophysical properties within Langmuir-Blodgett (LB) films. The results obtained from steady-state absorption as well as fluorescence excitation and emission measurements will be discussed with regard to interchromophoric interactions in the LB films. Time-resolved fluorescence inves6igations revealed the formation of a ground-state complex as well as excimer formation. Thermal treatment causes irreversible destruction of the LB film structure of the discotic amphiphiles. Within droplets the reorganization of the original nematic-discotic (ND) mesophase of the bulk materials was found for the alcohol 2 as indicated by a Maltese Cross texture, whereas the acid 1 remained isotopic. Y1 - 1995 ER - TY - JOUR A1 - Janietz, Dietmar A1 - Möbius, Dietmar A1 - Festag, R. A1 - Wendorff, Joachim Heinz A1 - Ahuja, Rajeev C. A1 - Reiche, Jürgen T1 - Supramolecular organization of amphiphilic discotic mesogens Y1 - 1994 ER - TY - JOUR A1 - Janietz, Dietmar A1 - Katholy, Stefan A1 - Dietzel, Birgit A1 - Brehmer, Ludwig T1 - Monolayer behaviour of two-fold hydroxy terminated sheet-like Tetrakis(phenylethynyl) benzene derivatives Y1 - 1997 ER - TY - JOUR A1 - Janietz, Dietmar A1 - Katholy, Stefan A1 - Brehmer, Ludwig T1 - Monolayer properties of Amphiphilic Tetrakis(phenylethynyl)benzene compounds Y1 - 1998 ER - TY - JOUR A1 - Janietz, Dietmar A1 - Hofmann, Dieter A1 - Reiche, Jürgen T1 - Molecular organization of amphiphilic disc-shaped penta-alkynes in LB-mono- and multilayers N2 - Amphiphilic disc-shaped penta-alkynes were studied with regard to their molecular organization in Langmuir-Blod- gett (LB) mono- and multilayers. It was found that each compound investigated forms edge-on arranged stable monolayers at the air-water interface. LB-multilayers derived from fivefold pentyl-substituted pentaynes are characterized by an edge-on ordering of the molecules within Y-type bilayers. One of these compounds, containing a hydoxy substituent as hydrophilic head group, is exemplified and two possible rectangular molecular assemblies perpendicular to the substrate, each with a columnar in-plane packing, will be discussed as a result of molecular modelling. Based on the experimental results, hexagonal layer packing in the LB-film of a disc-shaped penta-alkynyl carboxylic acid without lateral substituents proved to be possible, which, furthermore, could be confirmed by molecular mechanics simulation. Y1 - 1994 ER - TY - JOUR A1 - Janietz, Dietmar A1 - Hofmann, Dieter A1 - Reiche, Jürgen T1 - Reply to comment on "Molecular organization of amphiphilic disc-shaped penta-alkynes in LB mono- and multilayers" N2 - The model for the Langmuir-Blodgett (LB) film structure of amphiphilic disc-shaped penta-alkynes is refined. It is shown that LB experiments reported in a comment on one of our papers do not contradict the molecular organization within the LB films of the penta-alkynes we proposed. Y1 - 1995 ER - TY - JOUR A1 - Janietz, Dietmar A1 - Festag, R. A1 - Schmidt, C. A1 - Wendorff, Joachim Heinz T1 - Amphotropic oligomeric 1,3,5-triazines containing disc-shaped pentaalkyne and triphenylene side groups Y1 - 1996 ER - TY - JOUR A1 - Janietz, Dietmar A1 - Festag, R. A1 - Schmidt, C. A1 - Wendorff, Joachim Heinz T1 - Supramolecular assemblies of new amphotropic oligomers with disc-shaped side groups Y1 - 1995 ER - TY - JOUR A1 - Janietz, Dietmar A1 - Festag, R. A1 - Schmidt, C. A1 - Wendorff, Joachim Heinz T1 - Self-organization of new oligomers containing disc-shaped side groups Y1 - 1994 ER - TY - JOUR A1 - Janietz, Dietmar A1 - Festag, R. A1 - Schmidt, C. A1 - Tsukruk, V. V. A1 - Wendorff, Joachim Heinz T1 - Interfacial behaviour and thermal properties of triazine modified triphenylene oligomers Y1 - 1995 ER - TY - JOUR A1 - Janietz, Dietmar A1 - Ahuja, Rajeev C. A1 - Möbius, Dietmar T1 - Langmuir monolayers of sheet-shaped multialkyne amphiphiles Y1 - 1997 ER - TY - JOUR A1 - Janietz, Dietmar A1 - Ahuja, Rajeev C. A1 - Möbius, Dietmar T1 - Monomeric and oligomeric discotic amphiphiles at the air : water interface Y1 - 1994 ER -