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Updated: Dec 25, 2025
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Infrared Spectrum of Hydrobromic Aid
Summary
Precise infrared spectroscopy of hydrogen bromide (HBr) isotopes reveals distinct band centers for HBr79 and HBr81. Calculated rotational and vibrational constants align with prior research, confirming measurement accuracy.
Area of Science:
- Molecular Spectroscopy
- Physical Chemistry
- Isotope Analysis
Background:
- Hydrogen bromide (HBr) exists as two main isotopes, HBr79 and HBr81.
- Accurate spectroscopic data is crucial for understanding molecular properties and interatomic forces.
Purpose of the Study:
- To precisely measure the infrared fundamental bands of HBr79 and HBr81.
- To calculate and validate rotational and vibrational constants for these isotopes.
Main Methods:
- High-resolution infrared spectroscopy was employed to record the fundamental absorption bands.
- Spectral data was analyzed to determine band centers and derive molecular constants.
Main Results:
- The band centers for HBr79 and HBr81 were determined to be 2,558.94 cm⁻¹ and 2,558.56 cm⁻¹, respectively.
- Calculated rotational and vibrational constants show good agreement with previously reported values.
- Harmonic band centers (ωe) and anharmonicity constants (ωexe) were computed for both isotopes.
Conclusions:
- The study provides precise spectroscopic parameters for HBr isotopes.
- The results validate existing theoretical models and experimental data for HBr.
- Accurate spectroscopic constants enhance the understanding of HBr molecular dynamics.
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