Bond Type of bond Specific type of
bond
Absorption
peak
Appearance
C─H alkyl
methyl
1260 cm−1strong
1380 cm−1weak
2870 cm−1medium to strong
2960 cm−1medium to strong methylene
1470 cm−1strong
2850 cm−1medium to strong
2925 cm−1medium to strong methine2890 cm−1weak
vinyl
C═CH
2
900 cm−1strong
2975 cm−1medium
3080 cm−1medium
C═CH3020 cm−1medium
monosubstituted
stealth
alkenes
900 cm−1strong
990 cm−1strong
cis-disubstituted
alkenes
670–700
cm−1
strong
trans-disubstituted
alkenes
abc字母认识965 cm−1strong
trisubstituted
alkenes
800–840
cm−1
strong to medium aromatic
benzene/sub.
benzene
3070 cm−1weak
monosubstituted
benzene
700–750
cm−1
strong
690–710
cm−1
strong
ortho-disub.
benzene
750 cm−1strong
meta-disub. benzene
750–800
cm−1
strong
860–900
cm−1
strong
德国的首都para-disub. benzene
800–860
cm−1
strong
alkynes any 3300 cm−1medium aldehydes any
2720 cm−1
medium
2820 cm−1
C─C acyclic C─C
monosub. alkenes 1645 cm−1medium
1,1-disub. alkenes 1655 cm−1medium
cis-1,2-disub.
alkenes
1660 cm−1medium
trans-1,2-disub.
alkenes
1675 cm−1medium
trisub., tetrasub.
alkenes
1670 cm−1weak
ibt报名conjugated C─C
dienes
1600 cm−1strong
1650 cm−1strong
with benzene
ring英语拼写
1625 cm−1strong
with C═O1600 cm−1strong
C═C (both sp2) any
1640–1680
cm−1
medium
aromatic C═C any
1450 cm−1
weak to strong
(usually 3 or 4)
1500 cm−1
1580 cm−1
1600 cm−1
C≡C
terminal alkynes
2100–2140
cm−1
weak
disubst. alkynes
2190–2260
cm−1
very weak (often
indisinguishable)
C═O aldehyde/ketone
saturated
aliph./cyclic
6-membered
1720 cm−1
α,β-unsaturated 1685 cm−1
aromatic ketones 1685 cm−1
cyclic 5-membered 1750 cm−1
cyclic 4-membered 1775 cm−1
aldehydes 1725 cm−1
influence of
conjugation (as
with ketones)
carboxylic
acids/derivates
saturated
carboxylic acids
1710 cm−1
unsat./aromatic
carb. acids
1680–1690
cm−1
esters and lactones1735 cm−1
influenced by
conjugation and
ring size (as with ketones)
anhydrides 1760 cm−1 1820 cm−1
acyl halides1800 cm−1
split view
amides1650 cm−1associated amides
carboxylates (salts) 1550–1610 cm−1
amino acid zwitterions 1550–1610 cm−1
O─H alcohols,
phenols
low concentration
3610–3670
cm−1
high concentration
3200–3400
cm−1
broad
carboxylic
acids
low concentration
3500–3560
cm−1
high concentration 3000 cm−1broad
o专业培训
N─H primary amines any
3400–3500
cm−1
strong
1560–1640
cm−1
strong condary
amines
any >3000 cm−1weak to medium ammonium ions any
2400–3200
cm−1
multiple broad中秋 英语
peaks
C─O alcohols
primary
1040–1060
cm−1
strong, broad
condary ~1100 cm−1strong
tertiary
1150–1200
cm−1
medium
phenols any 1200 cm−1
ethers
aliphatic 1120 cm−1
aromatic
1220–1260
cm−1
carboxylic
acids
成考补习any
1250–1300
cm−1
esters any
1100–1300
cm−1
two bands
(distinct from
ketones, which do
not posss a C─O
bond)
C─N
aliphatic amines any 1020–1220
cm −1
often overlapped
C═N any
1615–1700
cm −1
similar
conjugation
eff ects to C═O C≡N (nitriles )
unconjugated
2250 cm −1 medium conjugated 2230 cm −1 medium R─N─C
(isocyanides ) any
2165–2110
cm −1
R─N═C═S
any 2140–1990
cm −1
C─X
fluoroalkanes
ordinary
1000–1100
cm −1
trifluromethyl
1100–1200 cm −1 two strong, broad bands chloroalkanes any 540–760ivyleague
cm −1
weak to medium
bromoalkanes any 500–600
cm −1 medium to strong
iodoalkanes
any
500 cm −1
medium to strong
N─O nitro compounds
aliphatic
1540 cm −1
stronger 1380 cm −1 weaker aromatic
1520, 1350 cm −1 lower if conjugated
