High resolution FTIR spectroscopy of fluoroform 12CHF3 and critical analysis of the infrared spectrum from 25 to 1500 cm−1

ABSTRACTWe report high-resolution ( 0.001 cm−1) Fourier Transform Infrared spectra of fluoroform (CHF3) including the pure rotational (far infrared or THz) range (28–65 cm−1), the ν3 fundamental ( = 700.099 cm−1), as well as the associated “hot’ band 2ν3 − ν3 ( = 699.295 cm−1) and the ‘atmospheric window’ range 1100–1250 cm−1 containing the strongly coupled polyad of the levels ν2, ν5 and ν3 + ν6, at room temperature and at 120 K using the collisional cooling cell coupled to our Bruker IFS 125 HR prototype (ZP2001) spectrometer and Bruker IFS 125 HR ETH-SLS prototype at the Swiss Light Source providing intense synchrotron radiation. The pure rotational spectra provide new information about the vibrational ground state of CHF3, which is useful for further analysis of excited vibrational states. The ν3 fundamental band is re-investigated together with the corresponding ‘hot’ band 2ν3 − ν3 leading to an extension of the existing line lists up to 4430 transitions with  = 66 for ν3 and 1040 transitions with  =...