红外常见官能团的特征吸收频率Bond Type of bond Specific type of
bond近亲无言
百乐门舞厅
Absorption
peak
Appearance
vfp试题C─H alkyl
methyl
1260 cm?1strong小学数学手抄报
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═CH2
900 cm?1strong
2975 cm?1medium
3080 cm?1medium
C═CH3020 cm?1medium
monosubstituted
alkenes
900 cm?1strong
990 cm?1strong
cis-disubstituted
alkenes
慈善征文670–700
cm?1
strong
trans-disubstituted
alkenes
965 cm?1strong
800–840
sa是什么岗位
cm?1
strong to medium aromatic
benzene/sub.
benzene
3070 cm?1weak
monosubstituted
benzene
700–750
cm?1
strong
690–710
cm?1人生最美是清欢
strong
ortho-disub.
benzene
750 cm?1strong
meta-disub. benzene
750–800
cm?1
strong
860–900
cm?1
strong
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
cis-1,2-disub.
alkenes
1660 cm?1medium
trans-1,2-disub.
alkenes
1675 cm?1medium trisub., tetrasub. alkenes
1670 cm?1weak conjugated C─C
dienes
1600 cm?1strong
1650 cm?1strong
with benzene
ring
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
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
amides1650 cm?1associated amides carboxylates (salts) 1550–1610 cm?1 amino acid zwitterions 1550–1610 cm?1
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
就前原则
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
peaks
C─O alcohols
primary
1040–1060
cm?1
strong, broad
condary ~1100 cm?1strong
tertiary
