The resonant charge transfer between H(-) ion and thin island films was investigated by the instrumentality of the wave-packet propagation method. Under the fixed island film size the ion level width, which characterizes the efficiency of electron transfer, is found to decrease exponentially with ion-surface distance increase. On the other hand the ion level width shows quantum-size effect when the island film radius is changing. The quantum-size effect can be verified experimentally by measuring the yield of charged atomic particles scattered or sputtered from thin metal island films. The necessary conditions for the quantum-size effect observation are low projectile velocity (under 0.01 a.u.) and small island film radius (under 100 a.u.). The thin island films can be obtained by means of electron stimulated desorption from dielectric surfaces. (C) 2011 Elsevier B.V. All rights reserved.