| Popis: |
The IR and Raman spectra of 2-methyl, 3-chloroaniline (2-M, 3-CA) and 2-methyl, 6-chloroaniline (2-M, 6-CA) have been recorded at room temperature in the region 3600-100 cm−1. A vibrational analysis has been made using additional frequencies obtained from IR studies at 223 and 123 K and also including the polarization measurement of the Raman lines. A comparative study of these two molecules together with the spectra of 2,3-dimethylaniline (2,3-DMA), investigated earlier, has been presented. The anomalous behaviour of certain normal modes at low temperatures indicates the presence of an intermolecular hydrogen bonding of the N-H…N type in 2-M, 3-CA and 2,3-DMA, whereas, in 2-M, 6-CA, an intramolecular hydrogen bonding of the type N-H…Cl has been detected owing to the presence of the highly electronegative Cl atom at the ortho position. |
