Unusual spectroscopic properties of CF3H dissolved in liquified Ar, N2, CO, and CO2

The FTIR spectra of CF3H have been studied in liquefied Ar, N2, CO, and CO2. The effect of a blue shift of frequency of the C–H stretching vibration accompanied by a decrease in the integral intensity of the corresponding ν1 band was found in the studied series of solvents. The combination bands ascribed to simultaneous excitation of vibrations of interacted molecular partners have been revealed in CO and CO2 solutions. DFT/B3LYP and ab initio MP2 calculations utilizing the 6-311++G(3df,3pd) basis set suggest weak linear F3CH⋯B complex formation, reproduce the experimentally observed unusual trends for B=Ar, N2, CO, CO2, and predict the conventional red frequency shift of the ν1 band for B=NH3.