title: The irradiation of ammonia ice studied by near edge x-ray absorption spectroscopy.
abstract: A vapor-deposited NH(3) ice film irradiated at 20 K with 150 eV photons has been studied with near-edge x-ray absorption fine structure (NEXAFS) spectroscopy at the nitrogen K-edge. Irradiation leads to the formation of high amounts (12%) of molecular nitrogen N(2), whose concentration as a function of the absorbed energy has been quantified to 0.13 molecule/eV. The stability of N(2) in solid NH(3) has been also studied, showing that N(2) continuously desorbs between 20 and 95 K from the irradiated ammonia ice film. Weak concentrations (<1%) of other photoproducts are also detected. Our NEXAFS simulations show that these features own to NH(2), N(2)H(2), and N(3)(-).
authors.affiliation: Laboratoire de Chimie Physique, CNRS, UMR 7614, Matière et Rayonnement, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05, France. philippe.parent@upmc.fr
authors.forename: Ph
authors.initials: P
authors.lastname: Parent
authors.forename: F
authors.initials: F
authors.lastname: Bournel
authors.forename: J
authors.initials: J
authors.lastname: Lasne
authors.forename: S
authors.initials: S
authors.lastname: Lacombe
authors.forename: G
authors.initials: G
authors.lastname: Strazzulla
authors.forename: S
authors.initials: S
authors.lastname: Gardonio
authors.forename: S
authors.initials: S
authors.lastname: Lizzit
authors.forename: J-P
authors.initials: JP
authors.lastname: Kappler
authors.forename: L
authors.initials: L
authors.lastname: Joly
authors.forename: C
authors.initials: C
authors.lastname: Laffon
authors.forename: S
authors.initials: S
authors.lastname: Carniato