Infrared identification of matrix isolated H2O.O2
Paul D Cooper1, Henrik G Kjaergaard, Vaughan S Langford
1Chemistry M313, School of Biomedical and Chemical Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
The Journal of Physical Chemistry. A
|July 13, 2006
Summary
Researchers experimentally identified the water-oxygen (H2O.O2) complex using infrared spectroscopy in a rare gas matrix. This finding, supported by theoretical calculations, is crucial for atmospheric and astrophysical chemistry.
Area of Science:
- Physical Chemistry
- Spectroscopy
- Computational Chemistry
Background:
- Previous theoretical studies explored the H2O.O2 complex.
- Experimental identification of the H2O.O2 complex remained elusive.
- The H2O.O2 complex is relevant to atmospheric and astrophysical processes.
Purpose of the Study:
- To experimentally identify the H2O.O2 complex.
- To characterize the vibrational properties of the H2O.O2 complex.
- To provide experimental data for theoretical models.
Main Methods:
- Co-deposition of H2O and O2 in argon matrices at 11.5 +/- 0.5 K.
- Infrared (IR) spectroscopy to detect absorption bands.
- Theoretical calculations using a harmonically coupled anharmonic oscillator local mode model.
- Ab initio calculation of the dipole moment function.
Main Results:
- Successful assignment of IR vibrations attributed to the H2O.O2 complex.
- Identification based on concentration-dependent behavior of absorption bands.
- Calculated OH-stretching and HOH-bending frequencies and intensities matched experimental observations.
Conclusions:
- The H2O.O2 complex has been experimentally identified for the first time.
- The study provides crucial experimental validation for theoretical predictions.
- The H2O.O2 complex's significance in atmospheric and astrophysical chemistry is highlighted.
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