Knowledge Bank

The infrared intensities of C-H stretching vibration bands of three chloroethylenes were measured in $CCl4$ and $CS2$ solutions. The photometric linearity of the spectrophotometer was checked with a rotary sector of variable aperture and the effect of scanning speed and slit width was investigated by use of the C-H out-of-plane vibration band of 1,2,4,5-tetrachlorobenzene as a standard band. The compounds investigated were trichloroethylene and cis- and trans-dichloroethylene. These were purified by vapor phase chromatography. The intensities observed in the liquid state were compared with those in the vapor state and the band shapes were examined in detail.