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Exploration of the potential energy surfaces, prediction of atmospheric concentrations, and prediction of vibrational spectra for the HO2...(H2O)n (n = 1-2) hydrogen bonded complexes.

ABSTRACT: The hydroperoxy radical (HO2) plays a critical role in Earth's atmospheric chemistry as a component of many important reactions. The self-reaction of hydroperoxy radicals in the gas phase is strongly affected by the presence of water vapor. In this work, we explore the potential energy surfaces of hydroperoxy radicals hydrogen bonded to one or two water molecules, and predict atmospheric concentrations and vibrational spectra of these complexes. We predict that when the HO2 concentration is on the order of 10(8) molecules x cm(-3) at 298 K, that the number of HO2...H2O complexes is on the order of 10(7) molecules x cm(-3) and the number of HO2...(H2O)2 complexes is on the order of 10(6) molecules x cm(-3). Using the computed abundance of HO2...H2O, we predict that, at 298 K, the bimolecular rate constant for HO2...H2O + HO2 is about 10 times that for HO2 + HO2.

SUBMITTER: Alongi KS

PROVIDER: S-EPMC2548419 | biostudies-literature | 2006 Mar

REPOSITORIES: biostudies-literature

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Exploration of the potential energy surfaces, prediction of atmospheric concentrations, and prediction of vibrational spectra for the HO2...(H2O)n (n = 1-2) hydrogen bonded complexes.

Alongi Kristin S KS Dibble Theodore S TS Shields George C GC Kirschner Karl N KN

The journal of physical chemistry. A 20060301 10

The hydroperoxy radical (HO2) plays a critical role in Earth's atmospheric chemistry as a component of many important reactions. The self-reaction of hydroperoxy radicals in the gas phase is strongly affected by the presence of water vapor. In this work, we explore the potential energy surfaces of hydroperoxy radicals hydrogen bonded to one or two water molecules, and predict atmospheric concentrations and vibrational spectra of these complexes. We predict that when the HO2 concentration is on t ...[more]

PMID: 16526652

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Dataset Information

Exploration of the potential energy surfaces, prediction of atmospheric concentrations, and prediction of vibrational spectra for the HO2...(H2O)n (n = 1-2) hydrogen bonded complexes.

Publications

Exploration of the potential energy surfaces, prediction of atmospheric concentrations, and prediction of vibrational spectra for the HO2...(H2O)n (n = 1-2) hydrogen bonded complexes.

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