title: Electron momentum spectroscopy study on valence electronic structures of ethylamine.
abstract: The valence-shell binding energy spectra and electron momentum profiles of gaseous ethylamine are measured by (e, 2e) electron momentum spectroscopy. When taking into account the Boltzmann-weighted abundance of 39% for trans and 61% for two equivalent gauche conformers coexisted in ethylamine, the thermally averaged electron momentum profiles for all valence orbitals calculated using B3LYP method with 6-311++G** and aug-cc-pVTZ basis sets reproduce the experimental ones well, which supports that the trans conformer is more stable. In addition, the controversial ordering of 2a'' and 7a' orbitals for the trans conformer is reassigned and an ionization band at about 13.7 eV, which was uncertain in previous literatures, is confirmed by comparing the experimental momentum profiles with the theoretical ones for the respective molecular orbitals. Furthermore, the ionization potentials and pole strengths for the inner valence orbitals are reported for the first time.
authors.affiliation: Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, China.
authors.forename: Mi
authors.initials: M
authors.lastname: Yan
authors.forename: Xu
authors.initials: X
authors.lastname: Shan
authors.forename: Fang
authors.initials: F
authors.lastname: Wu
authors.forename: Xuexin
authors.initials: X
authors.lastname: Xia
authors.forename: Kedong
authors.initials: K
authors.lastname: Wang
authors.forename: Kezun
authors.initials: K
authors.lastname: Xu
authors.forename: Xiangjun
authors.initials: X
authors.lastname: Chen
mesh_terms: D004583:Electrons; D005021:Ethylamines / Q000737:chemistry*; D008968:Molecular Conformation; D011789:Quantum Theory; D013057:Spectrum Analysis; D013237:Stereoisomerism; D013696:Temperature
chemical_list: D005021:Ethylamines; C041564:ethylamine