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Organic conducting materials exhibit promising functionalities, inducing hence a keen interest due to their potential use as a next generation photoconverters. However, unlike the more expensive inorganic analogues, the underlying properties that give rise to these advantages also cause organic materials to be inherently inefficient as photovoltaics. Understanding their properties at the microscopic level is a major step towards an efficient and targeted design. We probed the morphological and dynamical aspects of a model organic discotic liquid crystal material hexakis(n-hexyloxy)triphenylene (HAT6) by using neutron-based diffraction and quasielastic scattering techniques to gain deeper insights into structure and dynamics. The neutron measurements are accompanied, in a synergistic way, by molecular dynamics simulations for the sake of the analysis and interpretation of the observations.

International audience; The filled skutterudite CePt4Ge12 is reported to be at the border between an intermediate valence (IV) state and a Kondo lattice behavior. We report here the first inelastic neutron scattering experiments, carried out on the Ce compound and its non-magnetic counterpart LaPt4Ge12. Prior the neutron studies, the structural and magnetic properties of both samples have been determined. Inelastic neutron scattering spectra are dominated by phonon contribution for both compounds. A rattling vibration mode is observed at 6.9 meV and 7.5 meV for the Ce and La compounds, respectively. In CePt4Ge12 no crystal field excitation could be resolved. Only a small and wide extra contribution at high energy (22-28 meV) is observed. This result would be more consistent with an IV behavior.