Organic molecular systems, control

The Langmuir-Blodgett deposition is one of the best methods to prepare highly organized molecular systems, in which various molecular parameters such as distance, orientation, extent of chromophore interaction, or redox potential can be controlled in each monolayer. We have been studying... 

The LB deposition is one of the best methods to prepare highly organized molecular systems, in which various molecular parameters such as distance, orientation, extent of chromophore interaction, or redox potential can be controlled in each monolayer. We have been studying photophysical and photochemical properties of LB films in order to construct molecular electronic and photonic devices. The molecular orientation and interactions of redox chromophores are very important in controlling photoresponses at the molecular level. Absorption and fluorescence spectra give important information on them. We have studied photoresponses, specific interactions, and in-plane and out-of-plane orientation of various chromophores in LB films [3-11], In addition to the change of absorp-... 

Molecular chemistry has, thus, established its power over the covalent bond. The time has come to do the same for non-covalent intermolecular forces. Beyond molecular chemistry based on the covalent bond, lies the field of supramolecular chemistry, whose goal it is to gain control over the intermolecular bond [4-7]. It is concerned with the next step in increasing complexity beyond the molecule towards the supermolecule and large organized molecular systems, held together by non-covalent interactions. 

Beyond the spherical substrate, the next step in the control of molecular recognition and in the strategic elaboration of molecular systems displaying highly specific properties resides in the design of synthetic ligands for organic molecules, i. e. of synthetic molecular receptors 165). 

The modern tools available in synthetic chemistry, either from the organic viewpoint or concerning the preparation of transition metal complexes, allow one to prepare more and more sophisticated molecular systems. In parallel, time-resolved photochemistry and photophysics are nowadays particularly efficient to disentangle complex photochemical processes taking place on multicomponent molecules. In the present chapter, we have shown that the combination of the two types of expertise, namely synthesis and photochemistry, permits to tackle ambitious problems related to artificial photosynthesis or controlled dynamic systems. Although the two families of compounds made and studied lead to completely different properties and, potentially, to applications in very remote directions, the structural analogy of the complexes used is striking. 

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