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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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