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Fourier Transform Infrared Emission Spectroscopy of SeH
Journal of Molecular Spectroscopy
|August 10, 2000
Summary
This study measured the infrared vibration-rotation bands of selenium hydride (SeH) in its ground state. These measurements provide the first determination of the equilibrium molecular constants for the SeH X(2)Pi state.
Area of Science:
- Molecular Spectroscopy
- Physical Chemistry
- Quantum Mechanics
Background:
- Selenium hydride (SeH) is a diatomic molecule with limited spectroscopic data available.
- Understanding the electronic and vibrational properties of SeH is crucial for various chemical and physical applications.
- Previous studies have not fully characterized the equilibrium molecular constants of the SeH ground state.
Purpose of the Study:
- To measure and analyze the infrared vibration-rotation bands of SeH in its X(2)Pi ground state.
- To determine the equilibrium molecular constants for the X(2)Pi state of SeH.
- To provide the first comprehensive set of these constants for SeH.
Main Methods:
- Utilized a Fourier transform spectrometer for high-resolution spectral measurements.
- Generated SeH radicals in a microwave discharge of H(2) and Se in He.
- Observed rotational structure within specific vibrational bands (1-0, 2-1, 3-2 for X(2)Pi(3/2) and 1-0 for X(2)Pi(1/2)).
Main Results:
- Successfully measured infrared vibration-rotation bands of SeH in the 1800-2600 cm(-1) region.
- Determined key ground state molecular constants, including vibrational frequencies (omega(e), omega(e)x(e), omega(e)y(e)) and rotational constants (B(e), alpha(e)).
- Calculated the equilibrium bond length (r(e)) to be 1.464319(64) Å.
Conclusions:
- This work presents the first experimental determination of the equilibrium molecular constants for the X(2)Pi state of SeH.
- The obtained spectroscopic constants provide valuable data for theoretical calculations and understanding the SeH molecule.
- The results contribute to the broader field of diatomic molecular spectroscopy and the study of main group hydrides.
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