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

Journal Article · Tue Dec 15 04:00:00 EST 1987 · J. Chem. Phys.; (United States)

OSTI ID:6014634

Marshall, P; Fontijn, A

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), Journal Name: J. Chem. Phys.; (United States) Vol. 87:12; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COMBUSTION
DECOMPOSITION
DEUTERIUM
ELEMENTS
HIGH TEMPERATURE
HYDROGEN
HYDROGEN ISOTOPES
ISOTOPE EFFECTS
ISOTOPES
KINETICS
LIGHT NUCLEI
MEDIUM TEMPERATURE
NONMETALS
NUCLEI
ODD-ODD NUCLEI
OXIDATION
OXYGEN
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
REACTION KINETICS
STABLE ISOTOPES
THERMOCHEMICAL PROCESSES
VERY HIGH TEMPERATURE