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Updated: Aug 1, 2026
08:12
Synthesis and Operation of Fluorescent-core Microcavities for Refractometric Sensing
Published on: March 13, 2013
Extending ATOFMS measurements to include refractive index and density.
Ryan C Moffet1, Kimberly A Prather
1Department of Chemistry and Biochemistry, Scripps Institution of Oceanography, University of California, San Diego 9500 Gilman Drive, La Jolla, California 92093-0314, USA.
Analytical Chemistry
|October 15, 2005
Summary
This study calibrates aerosol light scattering measurements, linking particle chemistry to optical properties. This improves climate models by using single-particle data instead of bulk assumptions.
Area of Science:
- Atmospheric Science
- Spectroscopy
- Physical Chemistry
Background:
- Climate models rely on bulk aerosol data, necessitating assumptions about particle mixing states.
- Accurate aerosol optical properties are crucial for climate modeling.
- Existing methods lack direct links between single-particle chemistry and optical behavior.
Purpose of the Study:
- To perform an absolute calibration of light scattering in an aerosol time-of-flight mass spectrometer (ATOFMS).
- To enable direct comparison of experimental light scattering intensity with theoretical predictions.
- To link single-particle chemical composition and physical properties to optical behavior for improved climate model inputs.
Main Methods:
- Absolute calibration of the ATOFMS light scattering region.
- Utilizing a fitting procedure to determine refractive index and density for spherical particles.
- Correlating scattering intensity with single-particle size and chemical composition data.
Main Results:
- Established a direct comparison between experimentally measured and theoretically predicted light scattering intensities.
- Demonstrated the ability to determine particle refractive index and density from scattering data.
- Linked particle size, chemical composition, and scattering intensity.
Conclusions:
- Directly testing climate model assumptions regarding particle mixing states is now possible.
- Single-particle chemical information can be used to derive optical properties of different particle classes.
- This approach enhances the understanding of aerosol particle chemical and physical property relationships.
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