New reduced dimensionality calculations of cumulative reaction probabilities and rate constants for the H + H[sub 2] and D + H[sub 2] reactions

Journal Article · Thu Aug 18 04:00:00 EDT 1994 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100084a013· OSTI ID:6914654

Wang, D; Bowman, J M ^[1]

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1. Emory Univ., Atlanta, GA (United States)

Several refinements to our reduced dimensionality/adiabatic bend theory of reactive scattering are presented and applied to the H + H[sub 2] and D + H[sub 2] reactions. First, the harmonic treatment of the three-atom bending energy is replaced by an accurate numerical calculation of the adiabatic bending energies. Second, the standard J-shifting approximation for linear transition states is replaced by an adiabatic calculation of the overall rotational energy. In addition, the J-shift approximation is reanalyzed for anharmonic bending motion of the transition state, and an obvious improvement is suggested. Cumulative reaction probabilities and thermal rate constants are calculated for H + H[sub 2] and D + H[sub 2] and compared to accurate quantum ones for selected values of the total angular momentum. Based on these comparisons and previous calculations it is concluded that the new treatment of the adiabatic bending energy is a more significant refinement of the reduced dimensionality theory than is the adiabatic treatment of overall rotation. The thermal rate constant is calculated for D + H[sub 2] using the new theory and compared with other previous calculations, a recent full-dimensional accurate one up to 900 K and with experiment up to 2000 K. 33 refs., 5 figs., 4 tabs.

• DOE Contract Number: FG05-86ER13568
• OSTI ID: 6914654
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 98:33; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics & Computers
ADIABATIC PROCESSES
CALCULATION METHODS
CHEMICAL REACTION KINETICS
COMPILED DATA
DATA
DEUTERIUM
ELEMENTS
ENERGY LEVELS
EXCITED STATES
HAMILTONIANS
HYDROGEN
HYDROGEN ISOTOPES
INFORMATION
ISOTOPES
KINETICS
LIGHT NUCLEI
MATHEMATICAL OPERATORS
NONMETALS
NUCLEI
NUMERICAL DATA
ODD-ODD NUCLEI
PROBABILITY
QUANTUM NUMBERS
QUANTUM OPERATORS
REACTION KINETICS
ROTATIONAL STATES
STABLE ISOTOPES