Potential minima energies and stable structures of ArnO3 (n = 1-21) van der Waals complexes are determined using a stochastic search method coupling to molecular dynamics simulations. A nonrigid molecular potential surface, together with pairwise-additive intermolecular potentials, is used. Pattern mechanisms are described for the structures in the energetic ground state, situation in which a microsolvation process is observed. Relaxation effects are characterized and second differences on the clusters binding energies are calculated. Relative stabilities of the structures are discussed and the sensitivity of some key structures with respect to perturbations on parameters of the potential energy surface is investigated. (C) 2009 Elsevier B.V. All rights reserved.