Berlin 2018 – wissenschaftliches Programm
O 101: Focus Session: Structural Dynamics in Nanoscale Materials, Probed by Ultrafast Electron Pulses II
O 101.1: Hauptvortrag
Donnerstag, 15. März 2018, 15:00–15:30, HE 101
Ultrafast Structural Dynamics in Organic Molecular Solids — •Heinrich Schwoerer — Max Planck Institut für Struktur und Dynamik der Materie, Hamburg, Germany
Research on functional organic materials is driven by their chemically tunable optoelectronic properties which have led to many commercial applications, notably including molecular semiconductors such as organic light emitting diodes (OLEDs) and organic photodetectors. Comprised of molecules with strong internal covalent bonds which determine the optical characteristics, the macroscopic electronic properties of such crystals are predominantly set by the structural order, which is in turn determined by weak intermolecular forces. This hierarchy of forces opens two approaches for structural dynamics investigations: making use of the crystalline phase of organic molecules to study photo-induced chemical reactions (within the limitations of the confinement), and, looking beyond the unit cell, observing the ultrafast microscopic dynamics responsible for photo-induced macroscopic phase transitions in the entire organic crystal. We will introduce intriguing properties of organic molecular crystals and present recent examples of either of these approaches.