We report here the first measurements of the momentum profile of highest occupied molecular orbital (HOMO) and the complete valence shell binding energy spectra of propene with impact energies of 600 and 1200 eV by a binary (e, 2e) spectrometer. The experimental momentum profile of the HOMO orbitals was compared with the theoretical momentum distributions calculated using Hartree-Fock and density functional theory methods with various basis sets. The discrepancy between experimental and theoretical data was explained using the distorted wave effects. (C) 2004 Elsevier B.V. All rights reserved.