Molecular Photonic Materials
The research is focused on the photochemistry and photophysics of supramolecular systems (often based on organometallic compounds) which are interesting because of fundamental properties (e.g. theory of electron and energy transfer) but also have potential applications (opto-electronic devices, sensors, luminescent markers, holography, solar energy conversion). The group is especially interested in the design and study of molecular devices such as switches and sensors, electroluminescent materials, photoactive dendrimers and molecular wires. Their properties are studied using stationary and time-resolved absorption and emission spectroscopy and (spectro)electrochemical methods
Molecular Excited States (MES)
In order to be able to manipulate the photoresponse of materials it is necessary to know and understand the photochemical and photophysical properties of individual molecules, and to investigate how these molecular properties are influenced by the environment. One line of research is therefore concerned with “high-resolution” spectroscopic studies on molecular systems. In the frequency domain, high-resolution studies are performed in the gas phase on isolated molecules that range from simple chromophores to large supramolecular systems such as rotaxanes and catenanes in order to investigate their electronic and geometric structure, how these are affected by energy absorption, and - ultimately - how these are related to their (photoactive) function. In the time-domain, high-resolution studies are mainly performed under non-isolated conditions with various femtosecond laser spectroscopic techniques in order to answer the question as to what the molecule does with the energy that is absorbed in the form of photons, i.e., we “watch the energy flow”. A second line of research is specifically concentrated on the dynamics of (organic) molecules in solution and/or solid state. Photoinduced electron transfer is an important theme in this research. It is an elementary chemical reaction that leads to important follow-up processes from the charge-separated states prepared, such as multistep electron transport, redox reactions, charge transfer emission, photocatalysis and large-amplitude molecular motions. A continuous effort is made to apply the know-how gained to the development of photonic molecular systems and materials with potential practical use. These comprise luminescent optical probes, materials with nonlinear optical properties, electroluminescent devices, and molecular switches. Microphotochemistry and microspectroscopy, including single-molecule detection, have proven to be exciting new experimental approaches to advance the research in these directions.
Molecules and Light in Individual Metal Nanostructures (MOLIMEN)
MOLIMEN is a challenging interdisciplinary research project, funded under the ERA-NanoSci programme. MOLIMEN brings together four teams (from France, Italy and the Netherlands) that have complementary expertise in synthetic chemistry, spectroscopy, and theory and computation. In brief, MOLIMENs aims are (1) to develop a comprehensive theoretical picture as well as practical computational models that describe in detail how nanometer-sized metal structures affect the fundamental photophysical processes of nearby molecules; (2) to prepare structurally well-defined assemblies of nano particles and molecules in which chromophores are deliberately placed in hot spots; and (3) to demonstrate individual particle detection of specifically enhanced photonic signals. For more information, visit www.molimen.eu.