The IR spectrum of a nitrile exhibits characteristic absorption bands that aid in its identification. The most prominent band is the strong peak in the range of 2220-2260 cm-1, corresponding to the stretching vibration of the nitrile group (C≡N). This band is generally sharp and intense, making it easily recognizable in the IR spectrum. Additionally, a weaker band may be observed around 1640-1690 cm-1, attributed to the bending vibration of the C≡N bond. These characteristic absorption bands provide valuable information for confirming the presence of a nitrile functional group in an unknown compound.
