The effect of beta-halogen substitutions on the thermal chemistry of 1-propanol over Ni(1 1 1) and Cu(1 1 1) single-crystal surfaces was investigated using the method of unity bond index-quadratic exponential potential (UBI-QEP). This method was employed to investigate the energetics of the catalytic conversion routes of the ad-molecule mainly at the zero-coverage limit by calculating activation barriers and enthalpy changes for surface reactions. The alcohol molecule can be oxidized partially and totally over the Ni surface, however, the molecule is rather inactive on Cu. The beta-halogen substitution makes extensive conversion of the alcohol possible on the Cu surface and changes conversion pathways on the Ni surface. It was found that halogen substitution as well as hydrogen bonding can affect the reactivity and conversion routes of the molecules on Ni and Cu surfaces. On account of energetic criteria, the predicted routes for decompositions and the TPD patterns for the surface species are in accord with the available experimental observations. (C) 2015 Elsevier B.V. All rights reserved.