Electron momentum spectroscopy of ethylene oxide

Complete valence shell electron separation energy spectra are measured for ethylene oxide by electron momentum spectroscopy at a total energy of 1000 eV. Momentum densities are obtained at two well separated momenta, one close to zero (p0.16 au), the other at p0.77 au, to highlight respectively the s and p symmetries. Many-body calculations of the separation energies and spectroscopic factors using Green function methods are carried out and compared with the data. The measured momentum densities are compared with momentum distributions calculated in the plane wave impulse approximation formalism using SCF orbital wavefunctions. The agreement between the measured momentum distributions and the calculated ones is, in general, fair, the present SCF wavefunction being demonstrably superior to an earlier double-zeta quality molecular wavefunction for the outermost valence 2b2 and 4a1 orbitals.