Veröffentlichungen
Nach Erscheinungsjahr...
| 2016-2018 | 2019-2021 | 2022-2024 | 2025-2026 |
| 2004-2006 | 2007-2009 | 2010-2012 | 2013-2015 |
| bis 1990 | 1991-1995 | 1996-2000 | 2001-2003 |
... oder nutzen Sie die
Neueste Veröffentlichungen
Anmol Arya, Solomon L. Joseph, Francois Vonau, Jean-Luc Bubendorff, Silvia Siegenführ, Laurent Simon, Günter Reiter. J. Phys. Chem. C, published online
In the course of electrospraying in a vacuum, polymers acquire electric charges, which are distributed along their backbone. Here, we demonstrate that these charges have a strong impact on the molecular ordering and spectroscopic properties of conjugated polymers when deposited on substrates with an insulating oxide layer. To this end, we electrosprayed varying amounts of poly(3-hexylthiophene) (P3HT) onto silicon substrates with oxide layers of different thickness. The resulting morphologies were explored by atomic force microscopy. The corresponding spectroscopic properties, including their changes in time upon illumination, were derived from photoluminescence (PL) measurements. On insulating substrates, charges were retained on the polymer chains, causing long-range electrostatic repulsion and the formation of largely separated droplet-like objects containing multiple chains. These objects exhibited significant PL intensities for photons with a wavelength (λ) less than ca. 600 nm, suggesting the lack of π–π stacking interactions between P3HT chains. (more...)
Reversible Metamorphosis of a Conjugated Polymer Induced by Photoexcitation
Solomon Joseph, Anmol Arya, Günter Reiter. Advanced Photonics Research 7 (2026) e202500311
Optoelectronic properties of materials are frequently examined through spectroscopic tools based on the absorption and emission of (visible) photons. Typically, one assumes that these transient characterization processes do not cause observable change of these properties because of the low power of the employed light sources. However, for flexible conjugated polymers in a medium of low viscosity, it is decidedly unclear whether photoexcitation of electrons on the backbone of a long polymer chain has an influence on macromolecular conformations and the corresponding intermolecular interactions. Here, we provide clear experimental evidence that continuous absorption of photons progressively causes persistent changes in the spectroscopic properties of conjugated polymers, accompanied by microscopically observable changes in their spatial distribution within a low-viscosity matrix. By contrast, all these changes were completely absent in nonilluminated parts of the same sample.(more...)
Temperature dependence of crystal – melt coexistence for supported polyethylene filaments
Da Huang, Thorsten Hugel, Bizan N. Balzer, Günter Reiter. Nature Communications 16 (2025) 11127
The broken symmetry of molecular interactions at interfaces is causing that crystals are often covered by a thin liquid layer of their own melt. Such crystal–melt coexistence can be related to phenomena of surface premelting, secondary nucleation and melting point depression, particularly important for small systems. Here, we employed intermittent-contact mode atomic force microscopy imaging on nanoscopic semi-cylindrical filaments of polyethylene on a substrate to observe that these filaments contained a crystalline core bounded by molten regions of rather uniform width, W_soft= (9 ± 2) nm at room temperature, which increased reversibly with temperature T. Filaments smaller than ca. 2∙W_soft (T) were completely molten. The values of W_soft (T) compared favorably with theoretically predicted characteristic length scales in the context of nucleation, surface premelting and the melting point depression of finite size crystals. Altogether, we show that these three phenomena are related and dominated by the intermolecular forces acting at crystal surfaces. (more...)
Liste der Veröffentlichungen
- Application of 15N Nuclear Reaction Technique for Hydrogen Analysis in Polymer Thin Films
- D. Endisch, F. Rauch, A. Götzelmann, G. Reiter, M. Stamm. Nuclear Instruments and Methods in Physics Research B62, 513 (1992)
- Use of Ellipsometry in a Study of the Surface Order in the Isotropic Phase of a Liquid Crystalline Polyacrylate
- S. Immerschitt, W. Stille, and G. Strobl. Macromolecules 25, 3227 (1992)
- Light-Scattering Study of Fluctuations oin Concentration, Density, and Local Anisotropy in Polystyrene Dioxane Mixtures
- T. Koch, G. Strobl, B. Stühn. Macromulecules 25, 6255-6261 (1992)
- Neutron-Scattering Study of Segmental Dynamics in the Disordered Regions of Partially Crystalline Polyethylene
- G. Hohlweg, B. Holzer, W. Petry, G. Strobl, B. Stühn. Macromolecules 25, 6248-6254 (1992)
- Ellipsometric microscopy: Imaging monomolecular surfactant layers at the air-water interface
- R. Reiter, H. Motschmann, H. Orendi, A. Nemetz, W. Knoll. Langmuir 8, 1784-1788 (1992)
- The Effect of Short and Long Range Interactions on the Break up and Dewetting of Thin Polymer Films
- G. Reiter. Proceedings of the MRS Fall meeting 1991, Boston, USA
- TOREMA - A Neutron Reflectometer at Jülich
- M. Stamm, S. Hüttenbach, G. Reiter. Physica B 173, 11 (1991)
- The Use of X-ray and Neutron Reflectometry for the Investigation of Polymeric Thin Films
- M. Stamm, G. Reiter, K. Kunz. Physica B 173, 35 (1991)
- The Interface between 2 Strongly Incompatible Polymers
- S. Hüttenbach, M. Stamm, G. Reiter, M. Foster. Langmuir 7, 2438 (1991)
- Initial Stages of Polymer Interdiffusion Studied by Neutron Reflectometry
- M. Stamm, S. Hüttenbach, G. Reiter, T. Springer. Europhys. Lett. 14, 451 (1991)
- Measurements of Polymer Diffusion Over Small Distances: A Check of Reptation Arguments
- G. Reiter, U. Steiner. J. Phys. (France) II 1, 659-671 (1991)
- Time Regimes in Polymer Interdiffusion Determined by Marker Movement
- G. Reiter, S. Hüttenbach, M. Foster, M. Stamm. Macromolecules 24, 1179 (1991)
- X-ray and Neutron Reflectometry for the Investigation of Polymer Diffusion
- G. Reiter, S. Hüttenbach, M. Foster, M. Stamm. Fresenius J. Anal. Chem. 341, 284-288 (1991)
- Molecular-Dynamics in Perfluoro-n-Eicosane. 3. Oscillatory and Diffusive Translational Motion
- T. Albrecht, R. Jäger, W. Petry, R. Steiner, G. Strobl, B. Stühn. Journal of Chemical Physics 95, 2817-2822 (1991)
- Molecular-Dynamics in Perfluoro-n-Eicosane. 2. Components of Disorder
- T. Albrecht, H. Elben, R. Jäger, M. Kimmig, R. Steiner, G. Strobl, B. Stühn, H. Schwickert, C. Ritter. Journal of Chemical Physics 95, 2807-2816 (1991)
- Molecular-Dynamics in Perfluoro-n-Eicosane. 1. Solid-Phase Behavior and Crystal-Structures
- H. Schwickert, G. Strobl, M. Kimmig. Journal of Chemical Physics 95, 2800-2806 (1991)
- Mesogenic 4-Methoxyphenyl 4-Hexyloxybenzoate
- W. Haase, H. Paulus, G. Strobl, W. Hotz. Acta Crystallographica C, Crystal Structure Communications 47, 2005-2006 (1991)
- Ellipsometric characterisation of Langmuir monolayer of “hairy-rod” polymeres at the air-water interface
- H. Motschmann, R. Reiter, R. Lawall, G. Duda, M. Stamm, G. Wegner, W. Knoll. Langmuir 7, 2743-2747 (1991)
- Comparative Study of Individual and Collective Rotational Motion in Mixtures of Liquid Crystalline Side Group Polymers and Low Molecular Weight Mesogens
- H. Seiberle, W. Stille and G. Strobl. Macromolecules 23, 2008 (1990)
- Interdiffusion of Polymer Thin Films as Determined by Scattering Techniques
- M. Stamm, D. Brautmeier, G. Reiter, M. Foster. Proceed. of the 48th ANTEC 1990 Dallas, USA on "Plastics in the Environment: Yesterday, Today and Tomorrow" 36, 825 (1990)