Adiabatic three-dimensional simulations of the IHI sup minus , BrHI sup minus , and BrHBr sup minus photoelectron spectra

Journal Article · Wed Jul 15 04:00:00 EDT 1992 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.463199· OSTI ID:7039060

Metz, R B; Neumark, D M ^[1]

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1. Department of Chemistry, University of California, Berkeley, California 94720 (United States) Chemical Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)

In order to better characterize the transition-state region for the I + HI, Br + HI, and Br + HBr reactions, the photoelectron spectra of IHI{sup {minus}}, IDI{sup {minus}}, BrHI{sup {minus}}, BrHBr{sup {minus}}, and BrDBr{sup {minus}} have been simulated using a three-dimensional adiabatic approach. This method of simulation uses a Born--Oppenheimer separation in time scales between the fast hydrogen-atom motion and the slow halogen-atom motion to greatly simplify the computation of the photoelectron spectrum. The resulting simulations are compared to the experimental photoelectron and threshold photodetachment spectra of these anions, and to exact'' simulations of the IHI{sup {minus}} and IDI{sup {minus}} spectra. The comparison with the exact simulations shows that the adiabatic method is reasonably accurate, and is a considerable improvement over previous approximate simulation schemes. Potential-energy surfaces for the I + HI and Br + HI reactions are evaluated based on a comparison between the simulated and experimental spectra. A three-dimensional surface for the Br + HBr reaction that reproduces the experimental photoelectron spectrum is constructed by extending a fitted collinear surface to three dimensions.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 7039060
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 97:2; ISSN JCPSA; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ADIABATIC APPROXIMATION
ANIONS
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
BROMINE
BROMINE COMPLEXES
BROMINE COMPOUNDS
CHARGED PARTICLES
CHEMICAL REACTIONS
COLLISIONS
COMPLEXES
ELECTRON SPECTROSCOPY
ELEMENTS
HALOGEN COMPOUNDS
HALOGENS
HYDRIODIC ACID
HYDROBROMIC ACID
HYDROGEN COMPOUNDS
INORGANIC ACIDS
IODINE
IODINE COMPLEXES
IODINE COMPOUNDS
IONS
MOLECULAR IONS
MOLECULE COLLISIONS
NONMETALS
PHOTOELECTRON SPECTROSCOPY
SIMULATION
SPECTROSCOPY
THREE-DIMENSIONAL CALCULATIONS