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Lamb-Dip Millimeter-Wave and High-Resolution Far Infrared Spectra of HCCF
1Dipartimento di Chimica "G. Ciamician,", Università di Bologna, Via Selmi 2, Bologna, 40126, Italy
Journal of Molecular Spectroscopy
|December 16, 1998
Summary
This study precisely measured the ground state rotational spectrum of fluoroacetylene (HCCF) using millimeter-wave and FIR spectroscopy. A more accurate centrifugal distortion constant (H0) was determined, refining molecular data.
Area of Science:
- Molecular Spectroscopy
- Quantum Chemistry
- Physical Chemistry
Background:
- Fluoroacetylene (HCCF) is a simple halogenated alkyne with limited spectroscopic data.
- Accurate molecular constants are crucial for understanding chemical bonding and interstellar chemistry.
Purpose of the Study:
- To precisely measure the ground state rotational spectrum of fluoroacetylene.
- To determine accurate rotational and centrifugal distortion constants for HCCF.
- To refine the value of the H0 centrifugal distortion constant.
Main Methods:
- High-resolution millimeter-wave and Far-Infrared (FIR) spectroscopy.
- Measurement of rotational transitions up to 1280 GHz and J = 65.
- Preparation of fluoroacetylene via a dc glow discharge.
Main Results:
- The ground state rotational spectrum of fluoroacetylene was successfully measured.
- Accurate rotational and centrifugal distortion constants were determined.
- A significantly refined value for the H0 centrifugal distortion constant (2.0 x 10^-4 Hz) was obtained, differing from previous measurements.
Conclusions:
- The refined molecular constants provide a more accurate description of fluoroacetylene's ground state rotational dynamics.
- This study enhances the understanding of molecular properties for small halogenated organic compounds.
- The improved data contributes to spectroscopic databases for chemical and astronomical applications.
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