Molecular magnetism is a very active and promising field of research. Several teams are currently trying to design new kinds of magnet (materials with ferromagnetic transition) made of light elements only. Two mains ways are under investigation: 1/ the design of supramolecular assemblies of small organic molecules 2/ the design of magnetic polymers. This second way is very promising, because it would enable one to design magnetic materials as films, plastics or fibers.

Rajca et al (Science, 2001) have already shown that designing a highly ferrimagnetic polymer is possible. Unfortunately the spin carriers used in their system are not stable above 200 K, which precludes any commercial application. Currently research are orienting towards other polymers, like doped polyanilins, whose spin carriers are stable up to room temperature.

The PhD thesis will focus on polyanilins and model compounds (cyclophans, oligomers, dendrimers), whose structures are chosen in order to promote magnetic interactions (on the basis of previous studies carried in our team). The PhD student will evaluate experimentally the magnetic properties of these systems by magnetization measurements using SQUID magnetometry and Pulsed Electron Spin Resonance. In addition to these experimental studies, DFT calculations will be performed to better understand in which way the chemical structure (funcitonnal groups, linear or branched polymer chain, oxidation state) modulates the coupling between electronic spins and the magnetic properties of these systems. This work will be done in close collaboration with the Pr. Kulszewicz-Bajer's team (Polytechnicum Institute, Warsaw). This group is a leader in the field of functionnalised polyanilines synthesis.