Dresden 2009 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 15: POSTERS Dynamics and Diffusion

CPP 15.4: Poster

Dienstag, 24. März 2009, 14:00–16:30, P3

Study of order/disorder transitions in β-hydroquinone clathrates with ²H-NMR and dielectric spectroscopy — •Andre Nowaczyk, Catalin Gainaru, Sebastian Schildmann, Burkhard Geil, and Roland Böhmer — Experimentelle Physik III, Fakultät für Physik, Technische Universität Dortmund

We are studying the behavior of the guest molecules in partly filled β-hydroquinone clathrates. If the cage occupation x is higher than a critical value x_c, these substances undergo an order/disorder transition at a composition dependent temperature. The advantage of these binary mixtures, when compared for example with plastic crystals, is their stable and well-defined crystal structure into which the guest molecules are embedded. We have grown crystals with acetonitrile or methanol as guest molecules for different occupation factors x. By applying a combination of deuteron nuclear magnetic resonance and dielectric spectroscopy we study the guest-guest interactions in dependence on the occupation factor x. Several ²H-NMR techniques were applied, comprising relaxation experiments as well as stimulated-echo measurements to gain information on different timescales.