IR spectra and properties of solid acetone, an interstellar and cometary molecule
Reggie L Hudson1, Perry A Gerakines1, Robert F Ferrante2
1Astrochemistry Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.
Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
|December 8, 2017
Summary
This study presents new infrared spectra and optical constants for amorphous and crystalline acetone. Researchers corrected a significant error in prior research, improving understanding of acetone
Area of Science:
- Spectroscopy
- Solid-state chemistry
- Physical chemistry
Background:
- Acetone exists in amorphous and crystalline forms with distinct physical properties.
- Accurate optical constants and band strengths are crucial for spectroscopic analysis and material science applications.
- Previous studies on acetone's infrared properties may contain inaccuracies.
Purpose of the Study:
- To present mid-infrared spectra and optical constants for amorphous and crystalline acetone.
- To report infrared band strengths and vapor pressures for the first time.
- To identify and correct errors in existing acetone spectroscopic data.
Main Methods:
- Acquisition of mid-infrared spectra for amorphous and crystalline acetone.
- Measurement of refractive index, density, vapor pressure, and sublimation enthalpy.
- Determination of infrared optical constants and band strengths.
- Comparison with gas-phase data and density-functional theory calculations.
Main Results:
- Novel infrared band strengths for amorphous and crystalline acetone are reported.
- Refractive index, density, vapor pressure, and sublimation enthalpy were measured.
- A significant 73% error in previous work was identified and corrected.
- Positions of 13C-labeled acetone were accurately measured.
Conclusions:
- This work provides a comprehensive dataset for amorphous and crystalline acetone.
- The corrected data enhances the reliability of spectroscopic analyses involving acetone.
- New insights into the physical and optical properties of acetone's solid phases are established.
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