Abstract
The Raman spectra of CH2Cl2, CH2Br2, and CH2I2 have been observed at 77° and 195°K. Band splitting due to the crystal field has been found for the Raman bands ν3, ν4, and ν9 of CH2Cl2 and for the band ν1 of CH2Br2. No apparent splitting has been observed for the Raman bands of CH2I2. The band splittings and frequency shifts of the intramolecular vibrations are discussed. The Raman bands due to the lattice vibrations have been obtained and tentative assignments are presented for some of the bands. Much temperature effect has been found on the Raman frequencies of the lattice vibrations.