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Infrared Spectroscopy Absorption Table

  • Page ID
    22645
  • The following table lists infrared spectroscopy absorptions by frequency regions.

    4000-3000 cm-1
    3700-3584 medium sharp O-H stretching alcohol free
    3550-3200 strong broad O-H stretching alcohol intermolecular bonded
    3500
    3400
    medium   N-H stretching primary amine  
    3400-3300
    3330-3250
    medium   N-H stretching aliphatic primary amine  
    3350-3310 medium   N-H stretching secondary amine  
    3300-2500 strong broad O-H stretching carboxylic acid usually centered on 3000 cm-1
    3200-2700 weak broad O-H stretching alcohol intramolecular bonded
    3000-2800 strong broad N-H stretching amine salt  
                 
    3000-2500 cm-1
    3333-3267 strong sharp C-H stretching alkyne  
    3100-3000 medium   C-H stretching alkene  
    3000-2840 medium   C-H stretching alkane  
    2830-2695 medium   C-H stretching aldehyde doublet
    2600-2550 weak   S-H stretching thiol  
                 
    2400-2000 cm-1
    2349 strong   O=C=O stretching carbon dioxide  
    2275-2250 strong broad N=C=O stretching isocyanate  
    2260-2222 weak   CΞN stretching nitrile  
    2260-2190 weak   CΞC stretching alkyne disubstituted
    2175-2140 strong   S-CΞN stretching thiocyanate  
    2160-2120 strong   N=N=N stretching azide  
    2150     C=C=O stretching ketene  
    2145-2120 strong   N=C=N stretching carbodiimide  
    2140-2100 weak   CΞC stretching alkyne monosubstituted
    2140-1990 strong   N=C=S stretching isothiocyanate  
    2000-1900 medium   C=C=C stretching allene  
    2000     C=C=N stretching ketenimine  
                 
    2000-1650 cm-1
    2000-1650 weak   C-H bending aromatic compound overtone
                 
    1870-1540 cm-1
    1818
    1750
    strong   C=O stretching anhydride  
    1815-1785 strong   C=O stretching acid halide  
    1800-1770 strong   C=O stretching conjugated acid halide  
    1775
    1720
    strong   C=O stretching conjugated anhydride  
    1770-1780 strong   C=O stretching vinyl / phenyl ester  
    1760 strong   C=O stretching carboxylic acid monomer
    1750-1735 strong   C=O stretching esters 6-membered lactone
    1750-1735 strong   C=O stretching δ-lactone γ: 1770
    1745 strong   C=O stretching cyclopentanone  
    1740-1720 strong   C=O stretching aldehyde  
    1730-1715 strong   C=O stretching α,β-unsaturated ester or formates
    1725-1705 strong   C=O stretching aliphatic ketone or cyclohexanone or cyclopentenone
    1720-1706 strong   C=O stretching carboxylic acid dimer
    1710-1680 strong   C=O stretching conjugated acid dimer
    1710-1685 strong   C=O stretching conjugated aldehyde  
    1690 strong   C=O stretching primary amide free (associated: 1650)
    1690-1640 medium   C=N stretching imine / oxime  
    1685-1666 strong   C=O stretching conjugated ketone  
    1680 strong   C=O stretching secondary amide free (associated: 1640)
    1680 strong   C=O stretching tertiary amide free (associated: 1630)
    1650 strong   C=O stretching δ-lactam γ: 1750-1700 β: 1760-1730
                 
    1670-1600 cm-1
    1678-1668 weak   C=C stretching alkene disubstituted (trans)
    1675-1665 weak   C=C stretching alkene trisubstituted
    1675-1665 weak   C=C stretching alkene tetrasubstituted
    1662-1626 medium   C=C stretching alkene disubstituted (cis)
    1658-1648 medium   C=C stretching alkene vinylidene
    1650-1600 medium   C=C stretching conjugated alkene  
    1650-1580 medium   N-H bending amine  
    1650-1566 medium   C=C stretching cyclic alkene  
    1648-1638 strong   C=C stretching alkene monosubstituted
    1620-1610 strong   C=C stretching α,β-unsaturated ketone  
                 
    1600-1300 cm-1
    1550-1500
    1372-1290
    strong   N-O stretching nitro compound  
    1465 medium   C-H bending alkane methylene group
    1450
    1375
    medium   C-H bending alkane methyl group
    1390-1380 medium   C-H bending aldehyde  
    1385-1380
    1370-1365
    medium   C-H bending alkane gem dimethyl
                 
    1400-1000 cm-1
    1440-1395 medium   O-H bending carboxylic acid  
    1420-1330 medium   O-H bending alcohol  
    1415-1380
    1200-1185
    strong   S=O stretching sulfate  
    1410-1380
    1204-1177
    strong   S=O stretching sulfonyl chloride  
    1400-1000 strong   C-F stretching fluoro compound  
    1390-1310 medium   O-H bending phenol  
    1372-1335
    1195-1168
    strong   S=O stretching sulfonate  
    1370-1335
    1170-1155
    strong   S=O stretching sulfonamide  
    1350-1342
    1165-1150
    strong   S=O stretching sulfonic acid anhydrous
    hydrate: 1230-1120
    1350-1300
    1160-1120
    strong   S=O stretching sulfone  
    1342-1266 strong   C-N stretching aromatic amine  
    1310-1250 strong   C-O stretching aromatic ester  
    1275-1200
    1075-1020
    strong   C-O stretching alkyl aryl ether  
    1250-1020 medium   C-N stretching amine  
    1225-1200
    1075-1020
    strong   C-O stretching vinyl ether  
    1210-1163 strong   C-O stretching ester  
    1205-1124 strong   C-O stretching tertiary alcohol  
    1150-1085 strong   C-O stretching aliphatic ether  
    1124-1087 strong   C-O stretching secondary alcohol  
    1085-1050 strong   C-O stretching primary alcohol  
    1070-1030 strong   S=O stretching sulfoxide  
    1050-1040 strong broad CO-O-CO stretching anhydride  
                 
    1000-650 cm-1
    995-985
    915-905
    strong   C=C bending alkene monosubstituted
    980-960 strong   C=C bending alkene disubstituted (trans)
    895-885 strong   C=C bending alkene vinylidene
    850-550 strong   C-Cl stretching halo compound  
    840-790 medium   C=C bending alkene trisubstituted
    730-665 strong   C=C bending alkene disubstituted (cis)
    690-515 strong   C-Br stretching halo compound  
    600-500 strong   C-I stretching halo compound  
                 
    900-700 cm-1
    880 ± 20
    810 ± 20
    strong   C-H bending 1,2,4-trisubstituted  
    880 ± 20
    780 ± 20
    (700 ± 20)
    strong   C-H bending 1,3-disubstituted  
    810 ± 20 strong   C-H bending 1,4-disubstituted or
    1,2,3,4-tetrasubstituted
     
    780 ± 20
    (700 ± 20)
    strong   C-H bending 1,2,3-trisubstituted  
    755 ± 20 strong   C-H bending 1,2-disubstituted  
    750 ± 20
    700 ± 20
    strong   C-H bending monosubstituted
    benzene derivative
     

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