Negative activation energy for the self-reaction of HO/sub 2/ in the gas phase. Dimerization of HO/sub 2/

Journal Article · Mon Jan 01 04:00:00 EST 1979 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100476a025· OSTI ID:5133840

Lii, R R; Gorse, Jr, R A; Sauer, Jr, M C; Gordon, S

Measurements of the rate constant for the self-reaction of hydroperoxyl radical, HO/sub 2/, were made over the temperature range of 276-400/sup 0/K. A pulse radiolysis technique using a 50-ns electron pulse of about 2-MeV incident energy in a system of 1200 torr of H/sub 2/ and 5 torr of O/sub 2/ created H atoms which were entirely converted to HO/sub 2/ within a few microseconds. The slower disappearance of the HO/sub 2/ radical was followed over ca. 1 ms by kinetic spectrophotometry at 230 nm. The negative activation energy for the reaction, HO/sub 2/ + HO/sub 2/ ..-->.. H/sub 2/O/sub 2/ + O/sub 2/, was explained on the basis of an unstable dimer intermediate H/sub 2/O/sub 4/.

• Research Organization: Argonne National Lab., IL
• OSTI ID: 5133840
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 83; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400600* -- Radiation Chemistry
BEAMS
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHEMISTRY
DECOMPOSITION
DIMERIZATION
ELECTRON BEAMS
ELEMENTS
HYDROGEN
HYDROPEROXY RADICALS
IRRADIATION
KINETICS
LEPTON BEAMS
LOW PRESSURE
MEDIUM PRESSURE
NONMETALS
OXYGEN
PARTICLE BEAMS
POLYMERIZATION
PULSED IRRADIATION
RADIATION CHEMISTRY
RADIATION EFFECTS
RADICALS
RADIOLYSIS
REACTION KINETICS