Adsorption and photodesorption of CO from single C60 molecules studied from first principles

We report on first ab initio results concerning the photodesorption of CO from a single C60 fullerene. The weak interaction makes the use of computationally demanding electron correlation methods mandatory and we present various approaches for reducing the computational effort. The calculated adsorption energy amounts to −8.5 kJ mol−1 for the electronic ground state. The photodesorption is assumed to result from a 5σ → 2π☆ excitation in the adsorbate. The interaction in the excited state is stronger and leads to an Antoniewicz-like desorption mechanism. We treated the desorption process quantum dynamically and calculated desorption probabilities and velocity distributions of the desorbing molecules.