Wavenumber (cm⁻¹)

Bond

Functional group

3257.7

O-H stretch, H-bonded

alcohols, phenols

2094.8

-C(triple bond)C-stretch

or N=C=S stretching

Alkynes or Isothiocyanate

1636.3

C=C stretching

or N-H bending

or C=C stretching

Conjugated alkene or Amines or Cyclic alkene

1390.3

C-H bending

or O-H bending

or N-O symmetric stretch

Alkane or Phenol, alcohol or Nitro