The adsorption characteristics of methanol and formaldehyde molecules on an ice Ih(0 0 0 1) proton disordered crystal surface are compared on the basis of classical molecular dynamics simulations at 210 and 250 K. More specifically, the saturation coverage, the configurations of the molecules in their adsorption sites and the corresponding adsorption energies have been determined. (C) 2004 Elsevier B.V. All rights reserved.