Adsorption of para-hydrogen on fullerenes

Adsorption of para-hydrogen on the outer surface of a single fullerene is studied theoretically, by means of ground state quantum Monte Carlo simulations. We compute energetics and radial density profiles of para-hydrogen for various coverages on a variety of small fullerenes. The equilibrium adsorbed solid monolayer is commensurate with the surface of the fullerene; as the chemical potential is increased, a discontinuous change is generally observed, to an incommensurate, compressible layer. Quantum exchanges of hydrogen molecules are absent in these systems.