The document discusses Fourier transform infrared spectroscopy (FTIR). It provides a brief history of FTIR, noting its development in the 1940s and initial applications in organic chemistry and petrochemistry. It explains that FTIR uses an interferometer to measure all infrared frequencies simultaneously, rather than individually as with dispersive instruments. The document outlines several FTIR techniques and principles, such as how the absorption of infrared radiation corresponds to molecular bonds, and describes the basic working of FTIR through interferometry and Fourier transformation to produce spectra for material identification.

1. Fourier Transform Infrared

3. FTIR
 History
 Introduction
 Theory
 Technique
 Principle
 Working
 Working Diagram
 Actual Diagram
 Graph

4. FTIR
 History
infrared spectrophotometers were developed in the US in the mid 1940s. Initially,
their applications were confined to R&D work on organic compounds, mainly in
the petrochemical field. The first Japanese instruments were manufactured in
1954 by the Applied Optics Research Institute, the predecessor of JASCO.

5. FTIR
 Introduction:
A Fourier Transform InfraRed (FT-IR) Spectrometer is an
instrument which acquires broadband Near InfraRed (NIR) to Far
InfraRed (FIR) spectra.

6. FTIR
 Theory of FTIR:
 FTIR spectrophotometry was developed in order to overcome the limitations
encountered with dispersive instruments.
 The main difficulty was the slow scanning process. A method for measuring all the
infrared frequencies simultaneously, rather than individually, was needed.
 A solution was developed which employed a very simple optical device called an
interferometer. The interferometer produces unique type of signal which has all
the infrared frequencies “ encoded” into it.

7. Techniques of FTIR
 Following techniques of FTIR used by university researches scientists and process
engineers
 Attenuated Total Reflectance (ATR)
 Specular Reflectance (SR)
 Reflection absorption (RA)
 Transmission (TR)
 Photoacoustic (PA)

8. FTIR
 Principle
Principle Of FTIR is that many gases absorb IR radiation at species-specific frequencies.
FTIR spectroscopy is a disperse method, which means that measurements are performed over
a broad spectrum instead of a narrow band of frequencies.
The absorption corresponds specifically to the bonds present in the molecule. The frequency
range are measured as wave numbers typically over range 400-600m-1.

9. FTIR
 Working of FTIR
The FTIR uses interferometry to record information about a material placed in the IR
beam. The Fourier Transform results in spectra that analysts can use to identify or quantify
the material.

10. FTIR
 Working diagram:

11. FTIR
 Actual diagram

12. FTIR
 Graph

13. FTIR
• Applications of FTIR
• Quality verification of incoming/outgoing materials
• Deformulation of polymers, rubbers, and other materials through thermogravimetric infra-
red (TGA-IR) or gas chromatography infra-red (GC-IR) analysis
• Microanalysis of small sections of materials to identify contaminants
• Analysis of thin films and coatings
• Monitoring of automotive or smokestack emissions
• Failure analysis

14. FTIR