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The high-resolution infrared spectrum of CHD279Br has been investigated by Fourier transform spectroscopy in the range 540–615 cm−1 at an unapodised resolution of 0.0035 cm−1. This spectral region is characterised by the ν6 fundamental (584.8510 cm−1), corresponding to C–Br stretching mode, and its hot band 2ν6−ν6 (578.4333 cm−1). The spectral analysis resulted in the identification of 3430 transitions (J' ≤ 73 and K'a ≤ 18) for the ν6 fundamental and 1212 transitions (J' ≤ 49 and K'a ≤ 11) for the hot band 2ν6−ν6. The assigned data have been fitted using the Watson's S-reduced Hamiltonian in the Ir representation and new constants for the ground state from about 24,600 combination differences and sets of parameters for the v6 = 1 and 2 vibrational states have been obtained. From spectral simulations the intensity ratio between 2ν6−ν6 and ν6 has been estimated to be 0.15 ± 0.02. High-quality ab initio calculations have also been performed at the CCSD(T) level of theory in order to support the experimental investigation through the calculation of molecular parameters relevant to ro-vibrational spectroscopy. [ABSTRACT FROM AUTHOR]

The high-resolution infrared spectrum of CHD279Br has been investigated by Fourier transform spectroscopy in the range 700–900 cm−1 at an unapodized resolution of 0.0035 cm−1. This spectral region is characterised by the absorptions of the ν5 (814.5185 cm−1) and ν9 (716.9649 cm−1) fundamental bands, corresponding to H–C–Br deformation and CD2 rocking modes, respectively. The ν5 vibration of symmetry species A′ gives rise to an a-/c-hybrid band with a predominant a-type component, while the ν9 mode of A′′ symmetry produces a b-type envelope. The spectral analysis resulted in the identification of 5290 (J′ ≤ 63 and Ka′ ≤ 13) and 1657 (J′ ≤ 53 and Ka′ ≤ 12) transitions for ν5 and ν9 bands, respectively. The assigned data were fitted using the Watson's S-reduced Hamiltonian in the Ir representation and the v5 = 1 and v9 = 1 state parameters up to the quartic centrifugal distortion terms have been obtained. From spectral simulations the dipole moment ratio |Δμa/Δμc| of the ν5 band has been determined to be 1.4 ± 0.1 while the intensity ratio between ν5 and ν9 fundamentals has been estimated to have a value of 4.3 ± 0.5. [ABSTRACT FROM AUTHOR]