Factors influencing the frequency and intensity

Strained ring systems can also lead to small alterations in the 

The splitting appears to depend to a very considerable degree upon the bond angle between the methyl groups. In systems in which the methyl groups are attached to an unsaturated carbon atom and 

The deformation frequency of the single CH bond of the wopropyl group is too weak to be of value for identification in the infra-red. However it gives rise to a band in the 1350—1330 cm region in the Raman spectrum which is readily identified. 

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