Experimental determination of [Delta][ital H][sup 0][sub [ital f]](HOBr) and ionization potentials (HOBr): Implications for corresponding properties of HOI

Journal Article · Mon Oct 31 23:00:00 EST 1994 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.468273· OSTI ID:7140577

Ruscic, B; Berkowitz, J ^[1]

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1. Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

The photoion yield curves of HOBr[sup +] and Br[sup +] from HOBr are presented. The adiabatic I.P. of HOBr is found to be 10.638[plus minus]0.003 eV. Autoionizing structure in HOBr[sup +] is tentatively assigned and leads to an adiabatic I.P. of the first excited ([ital A] [ital L][sup 2] [ital A][prime]) state of [similar to]11.46 eV. The 0 K threshold of Br[sup +] from HOBr (13.915[plus minus]0.018 eV) implies [ital D][sub 0](HO--Br)[le]2.101[plus minus]0.018 eV[equivalent to]48.45[plus minus]0.42 kcal/mol. Together with auxiliary thermochemistry, this value yields [Delta][ital H][sub [ital f]][sub 298][sup 0](HOBr) [ge] [minus]13.43 [plus minus] 0.42 kcal/mol, in excellent agreement with a recent [ital ab] [ital initio] value [minus]14.2[plus minus]1.6 kcal/mol. The resulting proton affinity of BrO is 163.8 kcal/mol. Trends observed in the properties of OX and HOX (X=F, Cl, Br) are utilized to infer new values for [Delta][ital H][sup 0][sub [ital f]](OI) and [Delta][ital H][sup 0][sub [ital f]] (HOI). Predictions are made for I.P.(HOI). Proton affinities of OX are seen to increase with heavier X, while the [ital X] [sup 2][ital A][double prime]--[ital A] [sup 2][ital A][prime] splitting decreases.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 7140577
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 101:9; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

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71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
ADIABATIC APPROXIMATION
AFFINITY
AUTOIONIZATION
BROMINE COMPOUNDS
BROMINE IONS
BROMINE OXIDES
CHALCOGENIDES
CHARGED PARTICLES
EARTH ATMOSPHERE
ENERGY
HALOGEN COMPOUNDS
HYDRIODIC ACID
HYDROBROMIC ACID
HYDROGEN COMPOUNDS
INORGANIC ACIDS
IODINE COMPOUNDS
IODINE OXIDES
IONIZATION
IONIZATION POTENTIAL
IONS
LAYERS
MOLECULAR IONS
OXIDES
OXYGEN COMPOUNDS
OZONE LAYER
PHOTOIONIZATION
STRATOSPHERE
TEMPERATURE ZERO K
THERMOCHEMICAL PROCESSES
THRESHOLD ENERGY
YIELDS