Integration in NMR
The measurement of the area under each NMR signal, which is proportional to the number of nuclei giving rise to it.
Formula / equation
area ∝ number of nuclei
Unit
Dimensionless
In depth
Integration gives the ratio of protons in each environment, which combined with the molecular formula fixes the absolute numbers. It is quantitatively reliable in proton NMR but not in routine carbon NMR, where relaxation times and the decoupling method distort the intensities.
Examples in the real world
Ethanol's integrals of 3:2:1 corresponding exactly to its CH₃, CH₂ and OH protons.