大型放射光施設 SPring-8

Speaker: Dr.Leila Noohinejad

Language: English

Affiliation: Photon Science, Deutsches Elektronen-Synchrotron (DESY), Hamburg, Germany.

Title: Determination of proton dynamics in modulated organic ferroelectric phase transitions using synchrotron X-ray diffraction at P24 beamline, DESY.

Abstract:
In recent years, high-energy diffraction beamlines have become standard at new synchrotron facilities adding powerful tools for materials characterization: in situ X-ray diffraction, high-resolution measurements for charge density studies, tracing phase transitions, and modulated structures at ambient and non-ambient conditions. Beamline P24 provides a powerful instrument for new applications making use of the superior properties of PETRA III. A brief overview of beamline P24, a dedicated facility for small-molecule crystallography at Deutsches Elektronen-Synchrotron DESY will be given.
The importance of using synchrotron X-ray diffraction for understanding the crystal chemistry and the functional properties will be presented using examples of the modulated organic ferroelectric, 5,5´-dimethyl-2,2´-bipyridine (55DMBP) and bromanilic acid (H2ba). I will present recent advances in the field of aperiodic molecular ferroelectrics with an emphasis on the links between incommensurability, intermolecular interactions, and, ferroelectric properties of the materials.