Our interest is focused on hybrid systems (4TCH3@SWCNT) composed by dimethyl-quaterthiophene encapsulated inside single wall carbon nanotubes, with two main questions (1) the structure and dynamic of the confined oligomer depending on the nanotube diameter (2)the nature of the interaction between the oligomer and the host nanotube (charge transfer?). Optical spectroscopied with support of TEM and simulation have shown that the diameter of the nanotube is influencing the number of molecule per section but also the competition of interaction guest/gest or guest/host. The aim of this proposal is to study the dynamic of the oligothiophene encapsulated inside the nanotube using inelastic neutron scattering for temperature range 2-320K (IN4, Lagrange-2K only). Compared to Raman spectroscopy, INS offers for this system a pure dynamic response with a great contrast between the host and the guest, which is essential for the determination of the influence of the confinment on the dynamics of the oligothiophene.