IR Spectroscopy Tutorial: Alcohols

Alcohols have characteristic IR absorptions associated with both the O-H and the C-O stretching vibrations. When run as a thin liquid film, or "neat", the O–H stretch of alcohols appears in the region 3500-3200 cm-1 and is a very intense, broad band. The C–O stretch shows up in the region 1260-1050 cm-1.

The spectrum of ethanol is shown below. Note the very broad, strong band of the O–H stretch (3391) and the C–O stretches (1102, 1055).