Mechanism of thermal electron attachment to NO/sub 2/

Journal Article · Sat Mar 15 04:00:00 EST 1986 · J. Chem. Phys.; (United States)

OSTI ID:6057635

Shimamori, H; Hotta, H

The mechanism of thermal electron attachment to NO/sub 2/ has been reexamined by observing the dependence of the attachment rates on the nature and the pressure of the environmental gases. Measurements for mixtures of NO/sub 2/ with rare gases, H/sub 2/, D/sub 2/, N/sub 2/, CO/sub 2/, and n-C/sub 4/H/sub 10/ all showed two-body pressure dependence of the attachment rates at buffer-gas pressures of about 10 to 100 Torr. They gave the same two-body rate constant of (1.13 +- 0.07) x 10/sup -10/ cm/sup 3/ molecule/sup -1/ s/sup -1/. The latter result disagrees with the data reported by Mahan and Walker in 1967. The present results indicate that the collisional electron detachment process introduced previously to interpret the effect of the nature of environmental gases should be negligible. We have also observed the decrease of the two-body rate constants at pressures below about 10 Torr for all the mixtures studied. This strongly suggests that the attachment mechanism is an ordinary two-step three-body process. The three-body rate constants then obtained are mostly of the orders of 10/sup -27/ cm/sup 6/ molecule/sup -2/ s/sup -1/ and do not differ much with nature of the third bodies. An autoionization lifetime of 1 x 10/sup -8/ s has been estimated for the transient-negative ion of NO/sub 2/. It has been found that even room light could cause appreciable decrease of the rate constants, probably through decomposition of NO/sub 2/ molecules. The discrepancy between the present results and the previous ones may be due to such an effect.

• Research Organization: Fukui Institute of Technology, 3-618 Gakuen, Fukui 910, Japan
• OSTI ID: 6057635
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 84:6; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ALKANES
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
COLLISIONS
DEUTERIUM
DISPERSIONS
ELECTRON ATTACHMENT
ELECTRON COLLISIONS
ELECTRON-MOLECULE COLLISIONS
ELEMENTS
HYDROCARBONS
HYDROGEN
HYDROGEN ISOTOPES
IONIZATION
ISOTOPES
LIGHT NUCLEI
MIXTURES
MOLECULE COLLISIONS
NITROGEN
NITROGEN COMPOUNDS
NITROGEN DIOXIDE
NITROGEN OXIDES
NONMETALS
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PRESSURE DEPENDENCE
STABLE ISOTOPES