IR Spectroscopy Flashcards
(23 cards)
O-H(ROH)
3600-3200 strong and broad
N-H
3600-3200 medium and broad, one for each N-H
O-H (RCO2H)
3600-2500 strong and very broad
C-H (sp)
3300-3200 strong
C-H (sp2)
3000-3200 Variable, depends on number of groups
C-H (sp3)
2850-3000 variable, depends on number of groups
O=C-H
2850-2750 two sharp peaks, may be masked
C=-N
2260-2220 medium
C=-C
2260-2100 medium narrow
C=C
1700-1600 medium, narrow
C=C (Ar)
1600-1500 two narrow peaks(aromatic overtones)
C=O
1800-1600 very strong
Polarity determines the intensity of absorbance how.
The more polar the bond, the more intense the absorbance
Ex. C-O bonds typically yield very intense absorbances.
Number of bonds determine the intensity of the absorbance how?
The more bonds that absorb at the same wave number will yield a more intense absorbance.
H-bonding determines broadness of absorbance how?
Bonds the have atoms involved in H-bonding will yield broad absorbances.
O-H bonds typically yield very broad absorbances.
Bond Strength determines wave number absorbance how?
The strong the bond, the higher the wave number.
Atomic mass determines the wave number how?
The lighter the atoms, the higher the wave number.
Wave number
Number of waves per unit distance (# of waves per cm)
Wavelength
Distance between wave crests
Frequency
of waves per unit of time(# of waves per second)
Spectroscopy
The study of the interaction of matter and electromagnetic radiation.
C-O
1250-1050 strong
C-N
1230-1020 medium
