@article{41993, author = {{Bayer, Frank M. and Hiltrop, Karl and Huber, Klaus}}, issn = {{0743-7463}}, journal = {{Langmuir}}, keywords = {{Electrochemistry, Spectroscopy, Surfaces and Interfaces, Condensed Matter Physics, General Materials Science}}, number = {{17}}, pages = {{13815--13822}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Hydrogen-Bond-Induced Heteroassembly in Binary Colloidal Systems}}}, doi = {{10.1021/la101831x}}, volume = {{26}}, year = {{2010}}, } @article{41995, author = {{Lages, S. and Michels, R. and Huber, Klaus}}, issn = {{0024-9297}}, journal = {{Macromolecules}}, keywords = {{Materials Chemistry, Inorganic Chemistry, Polymers and Plastics, Organic Chemistry}}, number = {{6}}, pages = {{3027--3035}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Coil-Collapse and Coil-Aggregation due to the Interaction of Cu2+ and Ca2+ Ions with Anionic Polyacylate Chains in Dilute Solution}}}, doi = {{10.1021/ma9027239}}, volume = {{43}}, year = {{2010}}, } @article{25971, abstract = {{Precipitation of zinc sulfide particles is a very rapid process, and monitoring of the particle growth is experimentally very demanding. Applying a liquid jet flow cell, we were able to follow zinc sulfide particle formation on time scales down to 10−5 s. The flow cell was designed in such a way that data acquisition on the microsecond time scale was possible under steady-state conditions along a liquid jet (tubular reactor concept), allowing SAXS data accumulation over a time scale of minutes. We were able to monitor the growth of zinc sulfide particles and found experimental evidence for very rapid particle aggregation processes within the liquid jet. Under the experimental conditions the particle growth is controlled by mass transfer: i.e., the diffusion of the hydrogen sulfide into the liquid jet.}}, author = {{Schmidt, Wolfgang and Bussian, Patrick and Lindén, Mika and Amenitsch, Heinz and Agren, Patrik and Tiemann, Michael and Schüth, Ferdi}}, issn = {{0002-7863}}, journal = {{Journal of the American Chemical Society}}, pages = {{6822--6826}}, title = {{{Accessing Ultrashort Reaction Times in Particle Formation with SAXS Experiments: ZnS Precipitation on the Microsecond Time Scale}}}, doi = {{10.1021/ja101519z}}, year = {{2010}}, } @article{25967, abstract = {{We report the structural characterization and gas sensing properties of mesoporous SnO2 synthesized by structure replication (nanocasting) from ordered mesoporous KIT-6 silica. The products show a high thermal stability with no structural loss up to 600 °C and only minor decrease in specific surface area by 18% at 800 °C, as proven by powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), and nitrogen physisorption. In particular, the samples turn out to be much more stable than porous SnO2 materials prepared by sol–gel-based synthesis procedures for comparison. The thermal stability facilitates the utilization of the materials as sensors for combustible gases which react at high temperatures; test measurements reveal promising responses to methane (CH4) as an example.}}, author = {{Waitz, T. and Becker, B. and Wagner, T. and Sauerwald, T. and Kohl, C.-D. and Tiemann, Michael}}, issn = {{0925-4005}}, journal = {{Sensors and Actuators B: Chemical}}, pages = {{788--793}}, title = {{{Ordered nanoporous SnO2 gas sensors with high thermal stability}}}, doi = {{10.1016/j.snb.2010.08.001}}, year = {{2010}}, } @article{25972, abstract = {{In2O3 with ordered, uniform mesoporosity is prepared by nanocasting, using various porous silica phases (KIT-6, SBA-15) as structure matrices. The In2O3 particles exhibit well-defined morphologies (spherical or ellipsoidal, depending on the choice of silica matrix) and quite uniform sizes in the range of a few hundred nanometers. The regular morphology of the In2O3 particles is not associated with the morphological properties of the silica matrices. Instead, it is the result of the growth mechanism of In2O3 inside the silica pores; this mechanism is investigated in some detail. Hence, the nanocasting method offers a versatile and simple way of creating mesoporous In2O3 with regular morphology; this will be beneficial for many applications that require well-defined morphological properties, such as gas sensing or catalysis.}}, author = {{Haffer, Stefanie and Waitz, Thomas and Tiemann, Michael}}, issn = {{1932-7447}}, journal = {{The Journal of Physical Chemistry C}}, pages = {{2075--2081}}, title = {{{Mesoporous In2O3 with Regular Morphology by Nanocasting: A Simple Relation between Defined Particle Shape and Growth Mechanism}}}, doi = {{10.1021/jp910336f}}, year = {{2010}}, } @article{25968, abstract = {{We report the synthesis of monodisperse, spherical periodic mesoporous organosilica (PMO) materials. The particles have diameters between about 350 and 550 nm. They exhibit a regular core-shell structure with a solid, non-porous silica core and a mesoporous PMO shell with a thickness of approximately 75 nm and uniform pores of about 1.7 nm. The synthesis of the core and the shell is carried out in a one-pot, two-stage synthesis and can be accomplished at temperatures between 25 and 100 °C. Higher synthesis temperatures lead to substantial shrinking of the solid core, generating an empty void between core and shell. This leads to interesting cavitation phenomena in the nitrogen physisorption analysis at 77.4 K.}}, author = {{Haffer, Stefanie and Tiemann, Michael and Fröba, Michael}}, issn = {{0947-6539}}, journal = {{Chemistry - A European Journal}}, pages = {{10447--10452}}, title = {{{Periodic Mesoporous Organosilica (PMO) Materials with Uniform Spherical Core-Shell Structure}}}, doi = {{10.1002/chem.201000643}}, year = {{2010}}, } @inbook{25973, abstract = {{Chemical sensors are integral to the automation of myriad industrial processes, as well as everyday monitoring of such activities as public safety, engine performance, medical therapeutics, and many more...}}, author = {{Tiemann, Michael}}, booktitle = {{Nanostructured Materials}}, editor = {{Korotcenkov, Ghenadii}}, pages = {{291 -- 310}}, publisher = {{Momentum Press}}, title = {{{Ordered Mesoporous Films and Membranes: Synthesis, Properties and Applications in Gas Sensors}}}, volume = {{2}}, year = {{2010}}, } @article{38008, author = {{Werner, Thomas and Koch, Juliane}}, issn = {{1434-193X}}, journal = {{European Journal of Organic Chemistry}}, keywords = {{T3}}, number = {{36}}, pages = {{6904--6907}}, publisher = {{Wiley}}, title = {{{Sodium Hydride Catalyzed Tishchenko Reaction}}}, doi = {{10.1002/ejoc.201001294}}, volume = {{2010}}, year = {{2010}}, } @article{13843, author = {{Wippermann, S. and Schmidt, Wolf Gero and Thissen, P. and Grundmeier, Guido}}, issn = {{1862-6351}}, journal = {{physica status solidi (c)}}, number = {{2}}, pages = {{137--140}}, title = {{{Dissociative and molecular adsorption of water onα-Al2O3(0001)}}}, doi = {{10.1002/pssc.200982423}}, volume = {{7}}, year = {{2010}}, } @article{4123, abstract = {{GaAs-based semiconductor microdisks with high quality whispering gallery modes (Q44000) have been fabricated.A layer of self-organized InAs quantumdots (QDs) served as a light source to feed the optical modes at room temperature. In order to achieve frequency tuning of the optical modes, the microdisk devices have been immersed in 4 – cyano – 4´-pentylbiphenyl (5CB), a liquid crystal(LC) with a nematic phase below the clearing temperature of TC≈34°C .We have studied the device performance in the temperature rangeof T=20-50°C, in order to investigate the influence of the nematic–isotropic phase transition on the optical modes. Moreover,we havea pplied an AC electric field to the device,which leads in the nematic phase to a reorientation of the anisotropic dielectric tensor of the liquid crystal.This electrical anisotropy can be used to achieve electrical tunability of the optical modes.Using the finite-difference time domain (FDTD) technique with an anisotropic material model, we are able to describe the influence of the liquid crystal qualitatively.}}, author = {{Piegdon, Karoline A. and Offer, Matthias and Lorke, Axel and Urbanski, Martin and Hoischen, Andreas and Kitzerow, Heinz-Siegfried and Declair, Stefan and Förstner, Jens and Meier, Torsten and Reuter, Dirk and Wieck, Andreas D. and Meier, Cedrik}}, issn = {{1386-9477}}, journal = {{Physica E: Low-dimensional Systems and Nanostructures}}, keywords = {{tet_topic_qd, tet_topic_microdisk}}, number = {{10}}, pages = {{2552--2555}}, publisher = {{Elsevier BV}}, title = {{{Self-assembled quantum dots in a liquid-crystal-tunable microdisk resonator}}}, doi = {{10.1016/j.physe.2009.12.051}}, volume = {{42}}, year = {{2010}}, } @article{4172, abstract = {{Microdisks made from GaAs with embedded InAs quantum dots are immersed in the liquid crystal 4-cyano-4’-pentylbiphenyl (5CB). The quantum dots serve as emitters feeding the optical modes of the photonic cavity. By changing temperature, the liquid crystal undergoes a phase transition from the isotropic to the nematic state, which can be used as an effective tuning mechanism of the photonic modes of the cavity. In the nematic state, the uniaxial electrical anisotropy of the liquid crystal molecules can be exploited for orienting the material in an electric field, thus externally controlling the birefringence of the material. Using this effect, an electric field induced tuning of the modes is achieved. Numerical simulations using the finite-differences time-domain (FDTD) technique employing an anisotropic dielectric medium allow to understand the alignment of the liquid crystal molecules on the surface of the microdisk resonator.}}, author = {{Piegdon, Karoline A. and Declair, Stefan and Förstner, Jens and Meier, Torsten and Matthias, Heiner and Urbanski, Martin and Kitzerow, Heinz-Siegfried and Reuter, Dirk and Wieck, Andreas D. and Lorke, Axel and Meier, Cedrik}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{tet_topic_qd, tet_topic_microdisk}}, number = {{8}}, publisher = {{The Optical Society}}, title = {{{Tuning quantum-dot based photonic devices with liquid crystals}}}, doi = {{10.1364/oe.18.007946}}, volume = {{18}}, year = {{2010}}, } @article{58593, abstract = {{AbstractThe transition metal complexes with the ligand 1,3‐bis(N,N,N′,N′‐tetramethylguanidino)propane (btmgp), [Mn(btmgp)Br2] (1), [Co(btmgp)Cl2] (2), [Ni(btmgp)I2] (3), [Zn(btmgp)Cl2] (4), [Zn(btmgp)(O2CCH3)2] (5), [Cd(btmgp)Cl2] (6), [Hg(btmgp)Cl2] (7) and [Ag2(btmgp)2][ClO4]2·2MeCN (8), were prepared and characterised for the first time. The stoichiometric reaction of the corresponding water‐free metal salts with the ligand btmgp in dry MeCN or THF resulted in the straightforward formation of the mononuclear complexes 1–7 and the binuclear complex 8. In complexes with MII the metal ion shows a distorted tetrahedral coordination whereas in 8, the coordination of the MI ion is almost linear. The coordination behavior of btmgp and resulting structural parameters of the corresponding complexes were discussed in an comparative approach together with already described complexes of btmgp and the bisguanidine ligand N1,N2‐bis(1,3‐dimethylimidazolidin‐2‐ylidene)‐ethane‐1,2‐diamine (DMEG2e), respectively.}}, author = {{Neuba, Adam and Herres‐Pawlis, Sonja and Seewald, Oliver and Börner, Janna and Heuwing, Andreas J. and Flörke, Ulrich and Henkel, Gerald}}, issn = {{0044-2313}}, journal = {{Zeitschrift für anorganische und allgemeine Chemie}}, number = {{15}}, pages = {{2641--2649}}, publisher = {{Wiley}}, title = {{{Systematische Studie zu den Koordinationseigenschaften des Guanidin‐Liganden Bis(tetramethylguanidino)propan mit den Metallen Mangan, Cobalt, Nickel, Zink, Cadmium, Quecksilber und Silber}}}, doi = {{10.1002/zaac.201000133}}, volume = {{636}}, year = {{2010}}, } @article{22610, author = {{de los Arcos de Pedro, Maria Teresa and Oelhafen, Peter and Mathys, Daniel}}, issn = {{0008-6223}}, journal = {{Carbon}}, pages = {{1977--1982}}, title = {{{The importance of catalyst oxidation for the growth of carbon nanotubes on Si substrates}}}, doi = {{10.1016/j.carbon.2009.03.049}}, year = {{2009}}, } @article{39752, author = {{Lorenz, A. and Kitzerow, Heinz-Siegfried and Schwuchow, A. and Kobelke, J. and Bartelt, H.}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{23}}, publisher = {{The Optical Society}}, title = {{{Photonic crystal fiber with a dual-frequency addressable liquid crystal: behavior in the visible wavelength range}}}, doi = {{10.1364/oe.16.019375}}, volume = {{16}}, year = {{2009}}, } @article{39748, author = {{Matthias, H. and Kitzerow, Heinz-Siegfried}}, issn = {{1542-1406}}, journal = {{Molecular Crystals and Liquid Crystals}}, keywords = {{Condensed Matter Physics, General Materials Science, General Chemistry}}, number = {{1}}, pages = {{127/[489]--136/[498]}}, publisher = {{Informa UK Limited}}, title = {{{Director Fields Around Spherical and Cylindrical Micro Particles in a Liquid Crystal Host}}}, doi = {{10.1080/15421400903060300}}, volume = {{508}}, year = {{2009}}, } @article{39747, author = {{Hoischen, A. and Benning, S. A. and Kitzerow, Heinz-Siegfried}}, issn = {{0021-8979}}, journal = {{Journal of Applied Physics}}, keywords = {{General Physics and Astronomy}}, number = {{1}}, publisher = {{AIP Publishing}}, title = {{{Electroconvection of liquid crystals: Tool for fabricating modulated polymer surfaces}}}, doi = {{10.1063/1.3055398}}, volume = {{105}}, year = {{2009}}, } @inproceedings{39746, author = {{Kitzerow, Heinz-Siegfried}}, booktitle = {{SPIE Proceedings}}, editor = {{Chien, Liang-Chy and Wu, Ming Hsien}}, issn = {{0277-786X}}, publisher = {{SPIE}}, title = {{{Blue phases come of age: a review}}}, doi = {{10.1117/12.813372}}, year = {{2009}}, } @inproceedings{40639, author = {{Goodby, J. W. and Bates, M. and Saez, I. M. and Gorecka, E. and Kitzerow, Heinz-Siegfried and Guillon, D. and Donnio, B. and Serrano, J.-L. and Deschenaux, R.}}, booktitle = {{Mater. Res. Soc. Symp. Proc. 1134}}, editor = {{Cheng, Z. and Zhang, Q. and Bauer, S. and Wrobleski, D. A.}}, title = {{{Liquid Crystal Nano-particles, LCNANOP – a SONS II Collaborative Research Project}}}, volume = {{1134}}, year = {{2009}}, } @article{41274, abstract = {{Abstract Yttrium methoxyethoxide Y(OEtOMe)3 is an important precursor for the sol-gel preparation of Y2O3-containing materials. Its aggregation degree and the clusters, formed in solution of 2-methoxyethanol and modified by the ligands Hacac, i PrOH and THF are studied by means of EXAFS spectroscopy. The cluster geometries of the formed complexes deviate from the well-known cyclic decameric structure of the crystalline solid Y(OEtOMe)3. A pentanuclear square-pyramidal framework, which was found for Y(OEtOMe)3, dissolved in 2-methoxyethanol in a previous study, is confirmed by a detailed discussion of the structural EXAFS parameters. While the addition of the Lewis bases i PrOH and THF does not change the aggregation degree and short range order of Y(OEtOMe)3 in solution, chelating Hacac causes a stepwise degradation of the original pentameric metal framework. Details of the degradation pathway as deduced from the EXAFS results are given, which could not be achieved by any other spectroscopic method so far. The yttrium coordination number and third cumulants, which are necessary to account for asymmetry in the individual shells, are used in order to identify structural changes of the samples in comparison with the initially formed Y5-complex.}}, author = {{Bauer, Matthias and Bertagnolli, Helmut}}, issn = {{2196-7156}}, journal = {{Zeitschrift für Physikalische Chemie}}, keywords = {{Physical and Theoretical Chemistry}}, number = {{8}}, pages = {{877--893}}, publisher = {{Walter de Gruyter GmbH}}, title = {{{Alkoxide Clusters in Solution: An EXAFS Study of the Example Y(OEtOMe)3 and the Degradation Induced by Structural Modifiers}}}, doi = {{10.1524/zpch.2009.5474}}, volume = {{223}}, year = {{2009}}, } @article{41271, author = {{Rabe, Volker and Frey, Wolfgang and Baro, Angelika and Laschat, Sabine and Bauer, Matthias and Bertagnolli, Helmut and Rajagopalan, Subramanian and Asthalter, Tanja and Roduner, Emil and Dilger, Herbert and Glaser, Thorsten and Schnieders, David}}, issn = {{1434-1948}}, journal = {{European Journal of Inorganic Chemistry}}, keywords = {{Inorganic Chemistry}}, number = {{31}}, pages = {{4660--4674}}, publisher = {{Wiley}}, title = {{{Syntheses, Crystal Structures, Spectroscopic Properties, and Catalytic Aerobic Oxidations of Novel Trinuclear Non‐Heme Iron Complexes}}}, doi = {{10.1002/ejic.200900516}}, volume = {{2009}}, year = {{2009}}, }