Le vibrateur ch2, un auxiliaire approprié à l''étude structurale d''alcanes substttues par des groupements polaires : II. Polyhalogéno-propanes

The vibrational spectra of some polyhalogeno-propanes (1,3-dibromopropane. 1,2,3- trichloropropane, 1,2,3-tribromopropane, 1,2,2,3-tetrachloropropane) are investigated in the region 1400–1500 cm⁻¹. The results demonstrate that the bending mode frequency δ(CH₂) of a CH₂X group depends on the nature of the halogen X and on the direction in space of C-X' bonds located in the or position (CH₂X-CX'-). The application of these rules enables the conformation of 1,3-difluoropropane and 1,2,2,3-tetrabromopropane to be studied for the first time.