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Updated: Aug 9, 2026
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Characterization of Biological Absorption Spectra Spanning the Visible to the Short-Wave Infrared
Published on: January 10, 2025
Visible absorption spectrum of liquid ethylene
1Bell Laboratories, Murray Hill, New Jersey 07901.
Summary
Researchers measured the visible absorption spectrum of liquid ethylene using opto-acoustic spectroscopy. Ethylene
Area of Science:
- Spectroscopy
- Molecular Physics
- Physical Chemistry
Background:
- Ethylene (C2H4) is a fundamental molecule in chemistry and physics.
- Understanding its spectral properties is crucial for various applications.
- Previous studies have explored ethylene's vibrational and electronic spectra.
Purpose of the Study:
- To measure the visible absorption spectrum of liquid ethylene.
- To characterize the absorption bands and their coefficients.
- To propose assignments for the observed spectral features.
Main Methods:
- Opto-acoustic spectroscopy utilizing a pulsed tunable dye laser.
- Measurements were performed on liquid ethylene at approximately 108 K.
- The spectral range covered was from 5500 A to 7200 A.
Main Results:
- The visible absorption spectrum of liquid ethylene was successfully measured.
- Absorption features exhibited a range of absorption coefficients, from approximately 1 x 10(-4) cm(-1) to 2 x 10(-2) cm(-1).
- The strongest absorption band had a coefficient of approximately 2 x 10(-2) cm(-1).
Conclusions:
- The study provides detailed visible absorption data for liquid ethylene.
- Observed absorption peaks are proposed to arise from combinations of overtones of ethylene's local and normal modes of vibration.
- This research contributes to the understanding of molecular vibrational spectroscopy.
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