Introduction

  • The advantages and limitations of FTIR,
  • How an FTIR works,
  • Ways to measure instrument performance and spectral quality,
  • How spectral subtraction and library searching make the analysis of mixtures easier.


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Fundamentals of Fourier Transform Infrared Spectroscopy Module 1

Module 1: The Basics of FTIR
 
  • Introduction to Infrared Spectroscopy
  • The Properties of Light. What is an Infrared Spectrum? Y-Axis Units. What are Infrared Spectra Used for? Infrared Spectroscopy: Good and Bad Points
  • The Advantage of FTIR: Signal-to-Noise Ratio
  • The Disadvantage of FTIR: Water and CO2 Peaks


Fundamentals of Fourier Transform Infrared Spectroscopy Module 2

Module 2: How an FTIR Works

  • Interferometers and Interferograms
  • How a Spectrum is Produced
  • Optimizing Spectral Quality: Part 1


Fundamentals of Fourier Transform Infrared Spectroscopy Module 3

Module 3: How an FTIR Works

  • Optimizing Spectral Quality: Part 2
  •  FTIR Hardware
  • Infrared Sources, Beamsplitters, Detectors: DTGS and MCT, The He-Ne Laser
  • Instrument Troubleshooting


Fundamentals of Fourier Transform Infrared Spectroscopy Module 4

Module 4: Dealing with Mixtures

  • Spectral Subtraction
    • Theory
    • Optimizing Subtraction Results
    • Spotting Artifacts
  •  Library Searching
    •  Background and Theory
    • The Search Process
    • Properly Interpreting Search Results
    • Subtract and Search Again


Fundamentals of Fourier Transform Infrared Spectroscopy Module 5

Module 5 IR Sample Prep 1

  • I. Transmission Sampling
  • A. Advantages & Disadvantages
  • II. Transmission Sampling of Solids
  • A. KBr Pellets
  • 1. Sample Prep.
  • 2. Pellet Problems
  • B. Mulls
  • III. Transmission Sampling of Polymers
  • A. Casting Films
  • B. The Heat & Pressure Method
  • IV. Transmission Analysis of Liquids and Gases
  • A. Capillary Thin Films
  • B. Sealed Liquid Cells
  • C. Gases and Gas Cells

Fundamentals of Fourier Transform Infrared Spectroscopy Module 6

Module 6: IR Sample Prep II

  • I. Diffuse Reflectance (DRIFTS) for Solids and Powders
  • A. Sample Prep.
  • B. Applications
  • C. Abrasive Sampling
  • II. Attenuated Total Reflectance (ATR): A Technique for Many Samples
  • A. Theory & Background
  • B. Depth of Penetration
  • 1. Depth Profiling
  • 2. Quantitative Analysis
  • III. Applications of ATR
  • 1. Polymers
  • 2. Semi-Solids: Gels, Waxes, Pastes etc.
  • 3. Organic & Aqueous Liquids
  • 4. Powders

Fundamentals of Fourier Transform Infrared Spectroscopy Module 7

Module 7: Hyphenated Infrared Techniques

Technique names contain hyphens: GC-IR, TGA-IR

  • FTIRs can be interfaced to Microscopes, Gas Chromatographs, Liquid Chromatographs, and Thermogravimetric Analyzers
  • Hyphenated techniques provide multiple pieces of the information on the same sample at the same time
  • Need a special FTIR w “pickoff mirror” and hole in side of FTIR cover to interface with another piece of equipment