HTP kinetics studies of the reactions of O(2 /sup 3/P/sub J/) atoms with H/sub 2/ and D/sub 2/ over wide temperature ranges
The O+H/sub 2/(1) and O+D/sub 2/(2) reactions have been investigated, using the high-temperature photochemistry (HTP) technique, over the 350 to 1420 and 390 to 1420 K temperature ranges, respectively. O(2 /sup 3/P/sub J/) atoms were generated from flash photolysis of CO/sub 2/ and monitored by time-resolved atomic resonance fluorescence with pulse counting. Above 430 K the rate coefficients are given by k/sub 1/(T) = 7.3 x 10/sup -21/ (T/K)/sup 2.93/ exp(-2980 K/T) cm/sup 3/ molecule/sup -1/ s/sup -1/ and k/sub 2/(T) = 3.1 x 10/sup -16/ (T/K)/sup 1.65/ exp (-5260 K/T) cm/sup 3/ molecule/sup -1/ s/sup -1/. Combination of our data with those from other experiments which isolated the reactions from secondary processes yields our recommendations k/sub 1/(T) = 1.5 x 10/sup -12/ exp (-3540 K/T)+3.7 x 10/sup -10/ exp (-7450 K/T) cm/sup 3/ molecule/sup -1/ s/sup -1/ (300 Kless than or equal toTless than or equal to2500 K) and k/sub 2/(T) = 1.4 x 10/sup -12/ exp(-4260 K/T) +2.9 x 10/sup -10/ exp (-7780 K/T) cm/sup 3/ molecule/sup -1/ s/sup -1/ (390 Kless than or equal toTless than or equal to1420 K). Accuracy assessments are discussed in the text. k/sub 1/(T), k/sub 2/(T), and the kinetic isotope effect compare well with calculations based on recent ICVT/LAG and CEQB ab initio methods, which suggest that the first terms of the double exponential expressions approximate the tunneling contributions.
- Research Organization:
- Department of Chemical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180-3590
- OSTI ID:
- 6014634
- Journal Information:
- J. Chem. Phys.; (United States), Vol. 87:12
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
DEUTERIUM
CHEMICAL REACTION KINETICS
ISOTOPE EFFECTS
HYDROGEN
COMBUSTION
OXYGEN
HIGH TEMPERATURE
MEDIUM TEMPERATURE
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
VERY HIGH TEMPERATURE
CHEMICAL REACTIONS
DECOMPOSITION
ELEMENTS
HYDROGEN ISOTOPES
ISOTOPES
KINETICS
LIGHT NUCLEI
NONMETALS
NUCLEI
ODD-ODD NUCLEI
OXIDATION
REACTION KINETICS
STABLE ISOTOPES
THERMOCHEMICAL PROCESSES
400201* - Chemical & Physicochemical Properties