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Infrared spectroscopy of O?- and OH- in water clusters: evidence for fast interconversion between O?- and OH?OH.

ABSTRACT: We present infrared multiple photon dissociation (IRMPD) spectra of (H2O)nO?- and (H2O)nOH- cluster ensembles for n[combining macron] ? 8 and 47 in the range of 2400-4000 cm-1. Both hydrated ions exhibit the same spectral features, in good agreement with theoretical calculations. Decomposition of the calculated spectra shows that bands originating from H2OO?- and H2OOH- interactions span almost the whole spectral region of interest. Experimentally, evaporation of OH? is observed to a small extent, which requires interconversion of (H2O)nO?- into (H2O)n-1OH?OH-, with subsequent H2O evaporation preferred over OH? evaporation. The modeling shows that (H2O)nO?- and (H2O)n-1OH?OH- cannot be distinguished by IRMPD spectroscopy.

SUBMITTER: Lengyel J

PROVIDER: S-EPMC7100789 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Infrared spectroscopy of O˙- and OH- in water clusters: evidence for fast interconversion between O˙- and OH˙OH.

Lengyel Jozef J Ončák Milan M Herburger Andreas A van der Linde Christian C Beyer Martin K MK

Physical chemistry chemical physics : PCCP 20170901 37

We present infrared multiple photon dissociation (IRMPD) spectra of (H2O)nO˙- and (H2O)nOH- cluster ensembles for n[combining macron] ≈ 8 and 47 in the range of 2400-4000 cm-1. Both hydrated ions exhibit the same spectral features, in good agreement with theoretical calculations. Decomposition of the calculated spectra shows that bands originating from H2OO˙- and H2OOH- intera ...[more]

PMID: 28891582

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