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Updated: Feb 27, 2026
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In Situ Visualization of the Phase Behavior of Oil Samples Under Refinery Process Conditions
Published on: February 21, 2017
7.1K
An IR investigation of solid amorphous ethanol - Spectra, properties, and phase changes
1Astrochemistry Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.
Summary
Infrared spectra of amorphous ethanol were analyzed at low temperatures. This research provides key data for understanding ethanol
Area of Science:
- Astrochemistry
- Spectroscopy
- Condensed Matter Physics
Background:
- Ethanol (CH3CH2OH) is a molecule of significant interest in astrochemistry.
- Understanding the physical and chemical properties of condensed ethanol is crucial for interstellar medium research.
Purpose of the Study:
- To present mid- and far-infrared spectra of condensed ethanol (CH3CH2OH) across a temperature range of 10-160K.
- To focus on amorphous ethanol, its spectral characteristics, and phase transitions.
- To provide key physical parameters of amorphous ethanol relevant to astrochemical models.
Main Methods:
- Acquisition and analysis of mid- and far-infrared spectra of condensed ethanol.
- Temperature-dependent measurements from 10K to 160K.
- Characterization of both amorphous and crystalline phases of ethanol.
Main Results:
- Detailed infrared spectra for amorphous and crystalline ethanol are presented.
- Key physical properties including refractive index at 670nm, IR band strengths, and density for amorphous ethanol at 16K are reported.
- Spectral changes near the amorphous-to-crystalline transition (155-160K) were observed.
Conclusions:
- The study provides essential spectral data for amorphous ethanol, vital for astrochemical interpretations.
- Comparison with isoelectronic ethanethiol (CH3CH2SH) aids in understanding molecular behavior in astrophysical environments.
- The findings suggest potential applications for future astrochemical studies involving ethanol ice.
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