The 5-parameter morse potential (5-MP) of interaction between an adatom and metal surface cluster is put forward and performed on O-Ni single crystal surface systems. The data of adsorption sites, adsorption geometry, binding energy and eigenvalues for vibration, etc. are obtained, also, several controversial questions have been discussed and analyzed for these systems. The extended LEPS potential energy surfaces of CO-Ni single crystal plane systems are constructed by means of 5-MP, both the adsorption and vibration of CO on Ni low index plane surface and stepped defective surface are investigated. The predictions for adsorption geometry, binding energy and vibrational frequency, etc. that we obtained are in good agreement with the experimental results. Meanwhile, the influence of step defect on Ni(I 0 0) surface for CO dissociation is also examined. (C) 2002 Elsevier Science B.V. All rights reserved.