Improved potential energy surfaces for the reaction O(/sup 3/P)+H/sub 2/. -->. OH+H

Journal Article · Wed Jun 01 04:00:00 EDT 1988 · J. Chem. Phys.; (United States)

OSTI ID:5307177

Joseph, T; Truhlar, D G; Garrett, B C

We present global /sup 3/A' and /sup 3/A'' potential energy surfaces for the reaction O(/sup 3/P)+H/sub 2/..-->..OH+H and its isotopic analogs. The new surfaces are based in part on the surface of Lee et al. (J. Chem. Phys. 76, 3563 (1982)) for collinear O--H--H, which is modified to give accurate properties for reactants and products. The potentials for noncollinear O--H--H geometries are based on bending energies of Bowman et al. (J. Chem. Phys. 81, 1739 (1984)) as fit previously and called surface set M2 by two of the authors (B. C. Garrett and D. G. Truhlar, Int. J. Quantum Chem. 29, 1463 (1986)), and the potentials for H--O--H geometries are based on a new interpolation scheme. The new surfaces treat the approach of an O to either end of H/sub 2/ equivalently. We used improved canonical variational transition state theory calculations with the least-action ground-state tunneling approximation (ICVT/LAG) to recalibrate the classical barrier height to 13.0 kcal/mol. The ICVT/LAG rate constants calculated using the new surfaces are in excellent agreement with experimental values over the temperature range 298--2400 K. Rate constants and kinetic isotope effects for reactions involving D/sub 2/ and HD also are presented and analyzed. Here again, the theoretical results are in very good agreement with experiments.

• Research Organization: Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455
• OSTI ID: 5307177
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 88:11; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400800 -- Combustion
Pyrolysis
& High-Temperature Chemistry
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
COMBUSTION PRODUCTS
DEUTERIUM
ELEMENTS
HIGH TEMPERATURE
HYDROGEN
HYDROGEN ISOTOPES
HYDROXYL RADICALS
ISOTOPE EFFECTS
ISOTOPES
KINETICS
LIGHT NUCLEI
NONMETALS
NUCLEI
ODD-ODD NUCLEI
OXYGEN
RADICALS
REACTION KINETICS
STABLE ISOTOPES
VERY HIGH TEMPERATURE
YIELDS