Low-energy (less than or equal to 3 eV) electron attachment to molecules in very-high pressure gases: C/sub 2/H/sub 5/Br

Journal Article · Wed Oct 01 04:00:00 EDT 1975 · J. Chem. Phys.; (United States)

OSTI ID:7361078

Goans, R E; Christophorou, L G

Significant changes have been observed in both the magnitude and the energy dependence of the rate of attachment of slow (approximately equal to 3 eV) electrons to bromoethane (C/sub 2/H/sub 5/Br) in either N/sub 2/ or Ar gases with increasing density of these media from 500 to 25,000 torr for N/sub 2/ and from 500 to 42,000 torr for Ar. The observed density and energy dependences of the attachment rates are discussed on the basis of two plausible reaction schemes involving either one or two states of C/sub 2/H/sub 5/Br/sup -/. On the basis of the one-state reaction scheme, determinations were made of the absolute rate of formation of C/sub 2/H/sub 5/Br/sup -/* and of the relative magnitudes of the rates for dissociation and autoionization of the metastable C/sub 2/H/sub 5/Br/sup -/* ion as a function of the mean electron energy (epsilon). On the basis of the same reaction scheme, the lifetime of C/sub 2/H/sub 5/Br/sup -/* was estimated to be greater than or equal to13 psec in the mean energy range 0.3--1 eV. Although the vertical attachment energy for the C/sub 2/H/sub 5/Br molecule is approx.0.75 eV, the present results imply that its adiabatic electron affinity is positive (>0 eV). (auth)

• Research Organization: Oak Ridge National Lab., TN
• OSTI ID: 7361078
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 63:7; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
CHARGE EXCHANGE
COLLISIONS
ELECTRON ATTACHMENT
ELECTRON COLLISIONS
ELECTRON-MOLECULE COLLISIONS
ENERGY LEVELS
EXCITED STATES
METASTABLE STATES
MOLECULE COLLISIONS
ORGANIC BROMINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
PRESSURE DEPENDENCE