The irradiation of ammonia ice studied by near edge x-ray absorption spectroscopy.
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)(-).
Parent
Ph
P
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
Bournel
F
F
Lasne
J
J
Lacombe
S
S
Strazzulla
G
G
Gardonio
S
S
Lizzit
S
S
Kappler
J-P
JP
Joly
L
L
Laffon
C
C
Carniato
S
S