IR Spectroscopy 

Functional Group

  • Carboxylic Acid
    • with an alcohol
    • has an -OH stretch from 2500-3300cm-1
    • C double bond to O at 1700cm-1
  • Alcohol
    • strong stretch from 3200-3600cm-1
  • Aldehyde
    • Has a carbonyl group
    • C double bond to O at 1700com-1
    • C-H stretch at 2900cm-1
    • Is on the right side of the longer peak (C-H)
  • Ketone
    • Has a carbonyl group
    • C double bond to O at 1700cm-1
  • Ester
    • Has a carbonyl functional group
    • C double bond to O at 1700cm-1
    • higher wave bonds absorbs more
    • A Sp2 at the center of C
    • C-O stretch at 1200-1300cm-1
    • Sp3 at CH3
    • C-O at 1000-1150cm-1
  • Ether
    • Sp3 on the 3rd carbon
    • C double bond to O at 1000-1150cm-1

Degrees

  • Amine
    • Nh2- 1 degree
    • at 3300-3500cm-1
    • N-H - 2 degrees
    • at 3300-3500com-1
  • Amide
    • Has a carbonyl group
    • C-O stretch at 1700cm-1
    • C double bond to O stretch at 330-3500cm-1
    • tongue shaped

Hydrocarbons

  • Alkane
    • CH3
    • 2900 stretch
    • Sp3 at two peaks
    • CH3 bend at 1365-1385 with a little peak above the longer peak
  • Alkene
    • C double bond to C
    • A more thinner peak at 1660cm-1
    • CH at 3000-3100cm-1
    • peak is a little bit to the left side of the long two peaks with a C-H stretch and a sp2
  • Alkyne
    • C triple bond to C
    • at 2100-2200cm-1 with an even more smaller/thinner peak
    • peak is even more further away from the two peaks with a hybridization of sp