The far-infrared spectrum of 12C2HD

The infrared spectrum of 12C2HD has been studied using synchrotron radiation at the far-infrared beam line, Canadian Light Source, Saskatoon, Canada. The spectra were recorded at a resolution of 0.00096 cm1 in the 60 to 360 cm1 range using a Bruker IFS 125 Fourier transform spectrometer. In total, 821 vibration rotation lines were observed and assigned to the P(J), Q(J) and R(J) transitions of the 5 4 difference band and associated hot bands with J00 up to 35 and (4\ufe5) up to 3. These new transitions were analysed together with 4518 transitions involving bending states with (4\ufe5) up to 3 available in the literature. The spectroscopic parameters obtained from the fit reproduce 4909 transitions with a standard deviation of 0.00028 cm1. The 5 4 bands of 13CH12CD and 12CH13CD were also detected and analysed