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A Novel Technique for Raman Analysis of Highly Radioactive Samples Using Any Standard Micro-Raman Spectrometer
Published on: April 12, 2017
Spontaneous Raman scattering by ground-state oxygen atoms
Optics Letters
|August 25, 2009
Summary
Researchers observed Raman scattering by oxygen atoms for the first time, detecting specific electronic transitions in H(2) + O(2) flames. These findings provide new insights into atomic oxygen spectroscopy and combustion diagnostics.
Area of Science:
- Spectroscopy
- Physical Chemistry
- Combustion Science
Background:
- Raman scattering is a powerful technique for molecular analysis.
- Observing atomic oxygen via Raman scattering presents significant challenges due to its electronic structure and reactivity.
Purpose of the Study:
- To report the first observation of Raman scattering by oxygen atoms.
- To characterize the electronic transitions and measure scattering cross sections for atomic oxygen.
Main Methods:
- Utilized laser Raman spectroscopy in a fuel-lean atmospheric H(2) + O(2) flame.
- Detected Raman shifts corresponding to (3)P(2)?(3)P(1) and (3)P(2)?(3)P(0) transitions in atomic oxygen.
- Compared atomic oxygen electronic Raman scattering with O(2) pure-rotational Raman scattering.
Main Results:
- Successfully observed Raman scattering from oxygen atoms for the first time.
- Measured Raman shifts of 158 cm(-1) and 227 cm(-1) for two distinct atomic oxygen transitions.
- Determined polarized cross sections of (6 +/- 1) x 10(-31) cm(2)/sr and (4 +/- 1) x 10(-31) cm(2)/sr at 532.1 nm excitation.
- Observed cross sections were 2-3 times stronger than theoretical predictions.
Conclusions:
- This study demonstrates the feasibility of probing atomic oxygen using Raman spectroscopy.
- The measured cross sections provide crucial data for refining theoretical models of atomic oxygen scattering.
- This technique holds potential for advanced diagnostics in combustion and plasma environments.
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