The study of the cis-oleic acid adsorption, on clean and promoted (K, Mg, Co, B or Pd) PtNi(1 1 1) surface was performed by quatum chemical calculations. The oleic acid adsorption on PtNi(1 1 1) surface shows a weak molecule-surface interaction. No preferential site for C=C adsorption is computed and only the C=O adsorption is favored on the clean PtNi(1 1 1) surface. The adsorption properties of the PtNi(1 1 1) are improved by promoters. The stability of the system is increased and the C=C/surface distances are reduced when promoters are present. Among the considered promoters, Co has the best performance in terms of system stability. The lowest C p orbital substantially interacts with Pt and Co s, p and d orbitals. The change electron density of metal centers, enhance the C=C adsorption being the Pt-C interaction the more favored. After adsorption, the strength of the C=C, Pt Pt and Pt Co bonds decrease while a molecule-surface bond is formed. (C) 2012 Elsevier B. V. All rights reserved.