The adsorption of acrylonitrile (AN) on the different sites of Cu(100) surface has been studied theoretically by means of model copper cluster Cu₁₄(9,4,1) with density functional theory (DFT). AN standing up and adsorbed perpendicularly to the surface and bonded to the metal sites via a nitrogen-metal interaction took a weak chemisorption. Such chemisorption led to electron transfer from the AN molecule to the cluster. In the metal complexes of Cu₁₄-AN, the σ-bonding via the lone pair electrons on the N atom was observed. Chemisorption on top site was preferred with the adsorption energy of 40.7391 kJ•mol^－1 and the equilibrium N-surface distance of 0.2279 nm, while both bridge and hole sites were less stable than the top one, with their adsorption energies of 36.2513 and 30.2158 kJ•mol^－1, N-surface distances of 0.2194 and 0.2886 nm respectively. AN was activated by the chemisorption, which made the decrease of the strength of C≡N. The major contributions to the entropy decrease came from rotations and translations of AN, since these motions were lost upon chemisorption.

Key words: density functional theory, acrylonitrile, Cu(100) surface, chemisorption