Vibrational frequency splitting phenomenon

The consideration of two connected oscillators allows one to obtain conclusions of a general character. Thus, it has been shown that interactions between two natural vibrations that each have the same frequency (V = V2) lead to the frequencies splitting and a smearing of the amplitudes. This phenomenon is called resonance . In the presence of resonance, the vibration of an additive group spreads throughout the molecule and is not characteristic with respect to either form or frequency for the group. Resonance is often observed in molecular skeletal vibrations, and hence these are virtually always uncharacteristic for individual bonds. 

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