Vibration of Polymer Chains and Infrared Spectra

These waves possess the same vibrational energy (degeneracy). On the other hand, = 0 expresses the standing wave and is called in-phase vibration. 

When the line symmetry is broken down by the defects in the polymer chain, in principle, all vibrations will be optical active however, the intensity of the band depends strong on the local phase of the vibration. When the conformational order accompanying the ordering process of gelation and crystallization is studied by infiared and Raman spectroscopy, the relationship between the local phase lag and intensity is important. 

The value m depends on the mode and its value will be greater for the stronger interaction among the monomer units. 

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