Aniline molecules were state selectively detected using multiphoton ionization following trapping/desorption from amorphous C60 and C70 films, and from single-crystal C60 surfaces. Vibrational population inversion was observed in all three cases in the inversion mode of the NH2 group. The vibrational excitation was much less efficient for scattering from a LiF single-crystal surface. A charge-transfer model rationalizes the observations and indicates that the fullerene surfaces strongly interacts with molecules with low ionization potentials. © 1992 American Chemical Society.