1

What is it?

Chromatography

1

Spectroscopy

Spectrometry

Identify components

2

3

Separate mixture into components

Comparison to authentic samples

2

Infrared (IR) Spectroscopy

Identification of compounds

Based on molecular vibrations

Stretching and bending of chemical bonds

Energy change match that of IR light

3

Infrared (IR) Spectroscopy

Irradiate a molecule with IR

light of the correct frequency

Molecule starts to vibrate

4

Infrared (IR) Spectroscopy

Stretching frequency depends on

Masses of atoms involved

Stiffness of the bond

1

2

Single

bonds

Triple

bonds

Double

bonds

5

Infrared (IR) Spectroscopy

bonds to

H (light)

Triple bonds

(very stiff)

Double

bonds (stiff)

6

Infrared (IR) Spectroscopy

1500 cm

-1

Characteristic of the

class of compounds

7

Infrared (IR) Spectroscopy

Characteristic of the

individual compound

1500 cm

-1

1500 cm

-1

8

Infrared (IR) Spectroscopy

Molecular

fingerprint

Diamorphine

9

IR spectrum of diamorphine

“Fingerprint

region”

Diagnostic