The complexation in the gas-phase of several small organic compounds (C2H4H2O,CH2O,CO, HCOOH, HCONH2, NH3, CH3NH2. CH2NH and HCN) by Ag+ has been theoretically investigated using DFT calculations. Structural features are reported for the optimized geometries performed at the B3LYP density functional level of theory, using ECPs and a basis set augmented with one set of f functions. Final energies were evaluated using two sets of f functions. To assess the reliability of the method used, high correlation level methods (QCISD(T) and CCSD(T)) have been performed for some models. The computational binding energies have been compared to the available experimental ones. (C) 2001 Elsevier Science B.V. All rights reserved.