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What Are Some Types of Spectroscopy ?

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1 What Are Some Types of Spectroscopy ?
Dr Gihan Gawish What Are Some Types of Spectroscopy ? There are as many different types of spectroscopy as there are energy sources!

2 Dr Gihan Gawish Spectroscopy was originally the study of the interaction between radiation and matter as a function of wavelength (λ). In fact, historically, spectroscopy referred to the use of visible light dispersed according to its wavelength, e.g. by a prism.

3 Dr Gihan Gawish Later the concept was expanded greatly to comprise any measurement of a quantity as function of either wavelength (λ) or frequency. Spectroscopy is the measurement of the absorption, scattering, or emission of electromagnetic radiation by atoms or molecules.

4 Dr Gihan Gawish Absorption is the transfer of electromagnetic energy from a source to an atom or molecule. Scattering is the redirection of light as a result of its interaction with matter. Emission is the transition of electromagnetic energy from a one energy level to another energy level that results in the emission of a photon.

5 It is the carrier of electromagnetic radiation of all wavelengths
Dr Gihan Gawish The photon is the elementary particle responsible for electromagnetic phenomena. It is the carrier of electromagnetic radiation of all wavelengths

6 Dr Gihan Gawish Spectrometry is the spectroscopic technique used to assess the concentration or amount of a given species. In those cases, the instrument that performs such measurements is a spectrometer or spectrograph.

7 Dr Gihan Gawish Spectroscopy is often used in physical and analytical chemistry for the identification of substances through the spectrum emitted from or absorbed by them.

8 Dr Gihan Gawish A spectrophotometer consists basically of a radiant-energy source, monochromator, sample holder, and detector. It is used for measurement of radiant flux as a function of wavelength and for measurement of absorption spectra.

9 Nature of excitation measured
Types of Spectroscopy Dr Gihan Gawish Nature of excitation measured The type of spectroscopy depends on the physical quantity measured. Normally, the quantity that is measured is an intensity, either of energy absorbed or produced.

10 Electron spectroscopy involves interactions with electron beams.
Dr Gihan Gawish Electromagnetic spectroscopy involves interactions of matter with electromagnetic radiation, such as light. Electron spectroscopy involves interactions with electron beams. Mass spectrometry involves the interaction of charged species with magnetic and/or electric fields, giving rise to a mass spectrum.

11 Types of Spectroscopy Measurement process
Dr Gihan Gawish Measurement process Absorption spectroscopy uses the range of the electromagnetic spectra in which a substance absorbs. It is a technique in which the power of a beam of light measured before and after interaction with a sample is compared.

12 Absorption spectroscopy includes atomic absorption spectroscopy
Dr Gihan Gawish Absorption spectroscopy includes atomic absorption spectroscopy infrared spectroscopy nuclear magnetic resonance (NMR) spectroscopy in the radio region.

13 2. Emission spectroscopy
Dr Gihan Gawish 2. Emission spectroscopy It uses the range of electromagnetic spectra in which a substance radiates (emits). The substance first must absorb energy. like fluorescence spectroscopy

14 Scattering spectroscopy
Dr Gihan Gawish Scattering spectroscopy It measures the amount of light that a substance scatters at certain wavelengths, incident angles, and polarization angles. The scattering process is much faster than the absorption/emission process. One of the most useful applications of light scattering spectroscopy is Raman spectroscopy.


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