Vibrations of Methyl Groups Attached to Elements other than Carbon

Deformation vibrations of methyl groups attached to elements other than carbon 

The position of the CH3 symmetrical deformation frequency when the methyl group is attached to an element other than carbon is 

Bellamy and Williams [89] have pointed out that in any CH3X compound the individual CH frequencies are all directly related to one another and to the HX-stretching frequency. 

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