Vibrational dynamics of CO stretching in W(CO) 6-doped hybrid xerogels from 5 K to room temperature with the CLIO-FEL

One color pump–probe and photon-echo experiments have been performed on the CO stretching mode of W(CO) 6 at about 1982 cm −1 in organo-mineral xerogels. Over the whole temperature range studied, from room temperature to 5 K, the population lifetime T 1 remains constant when the vibrational dephasing time T 2 lengthens slightly. The temperature evolution of the pure dephasing time T ∗ 2 reveals two activation energies corresponding to molecular motions of the guest in the xerogel pore.