IR Spectra Flashcards
1
Q
A
3200–3600 (broad)
2
Q
A
2200–3600 (very broad)
3
Q
A
3350–3500
- Appears as a single broad
peak (but sharper than O-H)
4
Q
A
∼3300
5
Q
A
3000–3100
6
Q
A
2850–3000
7
Q
A
2750 and 2850 (two weak
signals)
8
Q
A
~1650–1820 (strong)
9
Q
A
1600–1700
10
Q
A
1450–1600
1650–2000
11
Q
A
2100–2200
12
Q
A
2200–2300
13
Q
A
C=O
~ 1820 and ~1760
14
Q
A
~1790
15
Q
A
~1735
16
Q
A
~1730
17
Q
A
~1720
18
Q
A
~1715
19
Q
A
~1650
20
Q
A
1250–1350
21
Q
A
1000–1100
22
Q
A
1000–1200
23
Q
A
600–800
24
Q
A
500–600
25
680- 860 cm-1 region can help determine ortho-meta-para substitution patterns for aromatics
26
The region between 1650-1800 for C=O
- carbonyl groups have a very strong, sharp, distinctive peak in the region around 1700 cm-1. The exact position of the C=O vibration varies somewhat according to the type of functional group
27
Primary Amines
3300-3500 cm-1
- often appears as two closely spaced peaks (sharper than O-H but still somewhat broad)
28
Terminal Alkyne
~ 3300 cm-1
- appears as a strong, sharp peak
29
____________________ appear as a broad peak with jagged edges that takes up the entire area of the spectrum, and often obscure the C-H stretching peaks around 3000 cm-1
Carboxylic acids
30
Most prominent and distinctive peaks to look for is the ________ absorbance around
3200-3500 cm-1
- It usually appears as a broad, featureless hump
OH
31
In IR spectroscopy, the sample (often a thin film) is exposed to a burst of infrared light, and the absorbance of the sample is measured versus the frequency of light.
