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Updated: Aug 14, 2026
10:22
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Determining aerosol temperatures by oxygen K-edge X-ray thermometry
Kay Carter-Fenk1,2,3, Slavomír Nemšák4,5, Sorren Warkander2
1Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA. kay.carter-fenk@pitt.edu.
Physical Chemistry Chemical Physics : PCCP
|August 13, 2026
Summary
Researchers developed X-ray thermometry to measure the temperature of cooling aerosol particles. This novel method reveals quantum nuclear effects and enhanced hydrogen bonding in glycerol aerosols, crucial for understanding aerosol cooling dynamics.
Area of Science:
- Physical Chemistry
- Materials Science
- Spectroscopy
Background:
- Measuring the temperature of rapidly evaporating aerosol particles is experimentally difficult.
- Conventional thermometry struggles to probe isolated droplets during nonequilibrium cooling.
Purpose of the Study:
- To combine near edge X-ray absorption fine structure (NEXAFS) with simulations to determine the temperature and structure of glycerol aerosols.
- To establish X-ray thermometry as a direct experimental method for studying rapidly cooling aerosols.
Main Methods:
- Utilized near edge X-ray absorption fine structure (NEXAFS) spectroscopy.
- Integrated NEXAFS data with computational simulations to analyze aerosol structure and temperature.
- Connected simulation-derived nuclear and electronic structure information with observed NEXAFS spectra.
Main Results:
- Quantum nuclear effects significantly influence the structure of glycerol aerosols.
- Observed a 'purple shift' phenomenon in NEXAFS spectra, broadening with decreasing temperature due to combined red- and blue-shifts.
- Identified enhanced hydrogen bonding in glycerol aerosols at approximately 175 K, below the glass transition temperature.
Conclusions:
- X-ray thermometry provides a direct experimental approach for probing the thermal and structural evolution of rapidly cooling aerosols.
- Quantum nuclear effects and hydrogen bonding play critical roles in aerosol behavior during cooling.
- The 'purple shift' is a temperature-dependent spectral feature linked to hydrogen bond strength in glycerol aerosols.
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