Optical properties of organic dyes
Modeling excited states energetic, electronic and structural properties is the necessary step in understanding and predicting phenomena such as photoisomerisation, photoreactivity, and luminescence. Our recent works shed the light on complex behavior of various types of organic molecules, providing rationalization for unexplained experimental events. In particular, we are focused on establishing structure-linear and non-linear optical properties relationship for various applications (laser printing, optical filters, imaging, optoelectronics, photovoltaics…) in close relation with experimentalists.
To do so, our theoretical tools are mainly based on the Time-Dependent Density Functional Theory (TD-DFT), up to higher level of theory when a wave function approach is needed (ADC2, CC2). These studies often require a description of the surrounding medium of the chromophore, depending on the experimental conditions, such as the solvent or a metallic support. More recently, our efforts have also been focused on the construction of more affordable computational schemes, using a tight-binding DFT approximation, allowing us to model photoactive systems of larger size and follow their excitation in time.
Keywords | Luminescence, TD-DFT, WFT, photovoltaics, non-linear properties, DFTB
People involved | Abdou Boucekkine, Arnaud Fihey, Claudine Katan, Boris Le Guennic
Performances of Density Functional Tight-Binding Methods for Describing Ground and Excited State Geometries of Organic Molecules
Synthesis of Bioinspired Curcuminoid Small Molecules for Solution-Processed Organic Solar Cells with High Open-Circuit Voltage
Transition metal-containing molecules: a gold mine for innovation
The group has many years of experience in the study of the electronic properties of metal containing molecules. Among the large range of physical properties currently investigated in the group, the photophysical, photochemical and magnetic properties of inorganic and coordination chemistry molecular systems have been the subject of intense research efforts recently by ICT. The ground state and excited state properties are explored using computational chemistry methods based on ab initio electronic structure theory and Density Functional Theory. Transition metal-containing molecules are offering a wide range of photo-physical and magnetic behaviors that one has to master to drive research toward applications such as low-cost and energy lighting, chemo-sensing, imaging, data storage, quantum computing. Quantum chemistry plays an important role in that domain by affording a deep understanding of physical properties that allows a computationally-assisted molecular design by making use of the diversity of chemical assemblies (modification of substituents, ligands, additional functionality...). Spin-orbit coupling plays an important role as revealed in our recent studies. Multiple emission, thermally-activated delayed fluorescence (TADF), magnetic anisotropy and magnetic coupling are for instance some of the phenomena we currently investigate. We also drive our efforts toward molecular devices such as molecular junction or modified surfaces.
Keywords | Transition metal, DFT, WFT, Luminescence, Molecular magnetism, Excited states, Photophysical properties
People involved | Abdou Boucekkine, Karine Costuas, Arnaud Fihey, Boris Le Guennic
Lanthanides complexes: magnetism, luminescence and chirality
People involved |
Ab Initio Study of Circular Dichroism and Circularly Polarized Luminescence of Spin-Allowed and Spin-Forbidden Transitions: From Organic Ketones to Lanthanide Complexes
Actinides complexes: catalysis and magnetism
People involved |
Luminescence polarisée circulairement de molécules aimants à base de lanthanide
Complexes organométalliques de lanthanides à relaxation magnétique lente
PEPS NanoPharE (2019)
Nanoparticle-supported molecular Photochromism for Harvesting solar Energy
Effet d'une irradiation lumineuse sur des ions aimants à transition de spin incorporant des ligands redox