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The High-Resolution Infrared Spectrum of 1,2,4-Triazine Vapor between 550 and 1700 cm(-1)
Thastum Bach D1, Hegelund, Beukes
1Department of Chemistry, Aarhus University, Aarhus C, DK-8000, Denmark
Journal of Molecular Spectroscopy
|November 30, 1999
Summary
High-resolution infrared spectroscopy of 1,2,4-triazine provided detailed assignments for fundamental bands. Spectroscopic constants were determined, offering insights into molecular structure and dynamics.
Area of Science:
- Molecular Spectroscopy
- Quantum Chemistry
- Physical Chemistry
Background:
- 1,2,4-triazine is a heterocyclic aromatic organic compound.
- Understanding its vibrational spectrum is crucial for molecular characterization.
Purpose of the Study:
- To assign fundamental vibrational bands of 1,2,4-triazine in the gas phase.
- To determine spectroscopic constants for the molecule.
Main Methods:
- Fourier transform infrared (FTIR) spectroscopy in the gas phase (550-1700 cm(-1)) at high resolution (0.003 cm(-1)).
- Comparison with liquid-phase IR and Raman spectra.
- Ab initio quantum chemical calculations.
- Analysis using the Watson Hamiltonian model.
- Ground state combination difference analysis.
Main Results:
- Assignment of most fundamental bands of 1,2,4-triazine below 1600 cm(-1).
- Determination of upper state spectroscopic constants for 12 fundamental bands.
- Identification and explanation of several local resonances.
- Obtained ground state rotational and centrifugal distortion constants.
Conclusions:
- The study successfully assigned key vibrational bands of 1,2,4-triazine.
- High-resolution gas-phase FTIR spectroscopy combined with theoretical calculations provides valuable molecular parameters.
- The obtained spectroscopic constants enhance the understanding of 1,2,4-triazine's structure and dynamics.
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