An investigation of the outer valance orbital electron density distribution of ethylene by electron momentum spectroscopy at 800 eV
Department of Physics, Tsinghua University, Beijing 100084, P.R. China
Published online: 3 May 2005
Electron density distributions in momentum space of the outer valence orbitals of ethylene are measured by electron momentum spectroscopy (EMS) in a non-coplanar symmetric geometry. The impact energy was 800 eV plus binding energy (8–22 eV) and energy resolution of the EMS spectrometer was 0.95 eV. The measured experimental momentum distributions of the outer valence orbitals are compared with Hartree-Fock and Density Functional Theory (DFT) calculations. The shapes of the experimental momentum distributions are generally quite well described by both the Hartree-Fock and DFT calculations when large and diffuse basis sets are used, except for 1 orbital. The experimental momentum profile of 1 orbital clearly show remarkable “turn up” in the low momentum region comparing with theoretical calculation and experimental results at impact energy of 1200 eV.
PACS: 34.80.Gs – Molecular excitation and ionization by electron impact
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005