Atomic emission spectroscopy is a technique that uses the intensity of light emitted from atoms excited by a heat source to determine the quantity of elements in a sample. The sample is converted to free atoms using a flame or electrothermal atomizer, then excited. A monochromator is used to selectively monitor the emission lines, and a detector measures the light intensity. This intensity is proportional to the number of atoms present. The technique can be used to identify and determine trace amounts of metals in samples like alloys and oils.

1. ATOMIC EMMISION
SPECTROSCOPY
SUBMITTED TO – KETAN SIR SUBMITTED BY – SHRADDHA YADAV
SVVV, Indore (M.P.)

2. WHAT IS SPECTROSCOPY ?
 Spectroscopy is the study of the interaction
between matter and electromagnetic
radiation.

4. WHAT IS ATOMIC SPECTROSCOPY ?
 Atomic spectroscopy is the study of the
electromagnetic radiation absorbed and emitted
by atoms . It is applied for determination of
elemental composition .

5. INTRODUCTION
ATOMIC EMMISION SPECTROSCOPY –
Is based upon emission of electromagnetic radiation
by atoms .

6.  AES is an analytical method that uses the intensity of light
emitted from atoms excited by a proper source at a
particular wavelength to determine the quantity of an
element in a sample .
 The wavelength of the atomic spectral line gives the
identity of the element while the intensity of the emitted
light is propotional to the number of atoms of the
element.

8. AES PRINCIPLE
 As in AAS the sample must be converted to free atoms , usually in a high
temperature excitation source .
 Liquid samples are nebulized and carried into the excitation source by a
flowing gas . Solid samples can be introduced into the source by a slurry or by
laser ablation of the solid sample in a gas stream .
 Solids can also be directly vaporized and excited by a spark between
electrodes or by a laser pulse .
 The excitation source must disolvate , atomize and excite the analyte atoms

9. Since the atomic emission lines are
very narrow , a high resolution
polychromator is needed to selectively
monitor each emission line.

10. SPECTRA OF AES

11. INSTRUMENTTION
1. ATOMIZER
2. MONOCHROMATOR
3. DECTECTORS

12. ATOMIZERS
 Elements to be analysed needs to be in atomic state , so atomization is done
 Atomization – is conversion of sample maybe solid or liquid into free gaseous
atom.
 Atomizer is a device used for atomization .
Are of two types –
1. Flame atomizer
2. Electro thermal atomizer

13. FLAME ATOMIZER
 To produce flame , mostly the air acetylene flame or nitrous oxide – acetylene
flame is used .
 Liquid or dissolved samples are typically used with flame atomizer
ADVANTAGES – reproducibility of sample and result
DISADVANTAGE – a minimum sample volume 0.5-1.0 ml needed to give a
reliable reading
- viscous samples require dilution with a solvent

14. SAMPLE HANDLING
 The droplets of sample introduced in the atomizer
should be of constant size
 The temperature should be maintained to obtain
good reproducibility
 Sufficient sample volume should be available for
maximum efficiency

15. MONOCHROMATORS
 It is a device use to transmit narrow band of
wavelength which is chosen from wavelength of
wider range available
 Types of monochromator are – prism and grating
monochromator

16. DETECTORS
 PHOTO TUBE DECTECTOR – glass filled or vacuum tube , sensitive to light ,
need amplifier and is replaced by photomultiplier detector .

17. ATOMIC EMISSION SPECTROMETERS
 Sensitivity is limited by noise
 High luminosity and high resolution monochromator necessary to isolate
spectral lines .
 Concave and plane grating use as dispersive element .
 Echelle grating system use for high resolution spectrograph .

18. Concave , plane and eschelle grating

19. APPLICATIONS
 It is used for elemental analysis
 It is used primarily for the identification and
determination of metals in traces amount .
 It is used for the analysis of sodium , potassium
and lithium .
 It is used for routine analysis of wear metals in
lubricating oils
 Analysis of ferrous and nonferrous alloys .