Organic and Organometallic Materials Chemistry

Organometallic light emitting molecules

Owing to their interesting luminescent properties, metal complexes have been intensively investigated during the last decade for applications in light emitting devices and solar cells. In this topic, we explore new design principles to achieve the appropriate electronic properties by devising appropriate metal-ligand interactions both in small molecules and polymers. In this context, we have recently developed novel classes of Pt(II), Au(I) and Au(III) organometallic molecules bearing different ancillary ligands that gave rise to complexes with exceptional thermal stability and phosphorescence properties. The judicious choice of the ligands allowed tuning of the emission properties. The excited state lifetimes coupled with their luminescent properties in the solid-state make these complexes promising for applications in OLEDs as the next generation triplet phosphors.

Electronic materials and molecular electronics

Azulene, a planar non - benzoic aromatic bicycle is an isomer of naphthalene. Owing to the small transition energy that arises from nonalternant polycyclic aromatic systems, azulene possess a deep blue color, which is remarkable for such a small conjugated system. It shows a very high dipole moment of 1.08 D because of the electrically positive seven-membered ring and an electrically negative five-membered ring. In this project, we aim to engineer the band-gap of azulene and its derivatives by tailoring the electronics through appropriate functionalization in order to achieve excellent redox active characteristics and luminescent properties. In collaboration with the group of Professor Berke (University of Zürich) and Dr. Heike Riel (IBM, Zürich), we are currently investigating the electronic properties of organic and organometallic molecules both as an ensemble of molecules and also at the single molecule level.

Catalyst design and development

Precise macromolecular synthesis of polymers is key to the development of advanced materials. For the final function, the performance and properties of polymeric materials are encoded in the microstructure and shape of individual well-defined synthetic macromolecules, which self-organize into nanophase separated morphologies. The definitive macroscopic properties of the prepared materials will depend on the molecular structure of individual chains assembled into nano-structured morphologies, and then into grains and clusters. Precise synthesis of polymers is of paramount importance among many parameters that have to be controlled in order to prepare the desired materials. In this project, we develop novel homogeneous catalysts that are able to aid in the development of new electronic polymers with precisely controlled molecular structure of the individual chains.