Infrared Spectroscopy

James M. Thompson

• Publisher: Jenny Stanford Publishing
• Year: 2018
• Print ISBN: 9789814774789
• eBook ISBN: 9781351206013
• Topic: Physical Sciences
• Subtopic: Biology

It is estimated that there are about 10 million organic chemicals known, and about 100,000 new organic compounds are produced each year. Some of these new chemicals are made in the laboratory and some are isolated from natural products. The structural determination of these compounds is the job of the chemist. There are several instrumental techniques used to determine the structures of organic compounds. These include NMR, UV/visible, infrared spectroscopy, mass spectrometry, and X-ray crystallography. Of all the instrumental techniques listed, infrared spectroscopy and mass spectrometry are the two most popular techniques, mainly because they tend to be less expensive and give us the most structural information.
This book is an introductory text designed to acquaint undergraduate and graduate students with the basic theory and interpretative techniques of infrared spectroscopy. Much of the material in this text has been used over a period of several years for teaching courses in materials characterization and chemical analysis. It presents the infrared spectra of the major classes of organic compounds and correlates the infrared bands (bond vibrations) of each spectrum with the structural features of the compound it represents. This has been done for hydrocarbons, organic acids, ketones, aldehydes, esters, anhydrides, phenols, amines, and amides. The text discusses the origin of the fragments, techniques, innovations, and applications in infrared spectroscopy. It is interspersed with many illustrations, examples, an adequate but not overwhelming bibliography, and problems for students. It will serve as a lecture text for a one-semester course in infrared spectroscopy or can be used to teach the infrared spectroscopy portion of a broader course in material characterization and chemical analysis.

Contents

Preface

Acknowledgment

1. Some Fundamentals of Infrared Spectroscopy

1.1 Introduction

1.2 The Energy of EIectromagnetic Radiation

1.3 Information That May Be Obtained from the Analysis of Infrared Spectra

1.4 Comparison Techniques

1.5 Fundamental Vibrations

1.5.1 StretchingVibrations

1.5.2 Bending Vibrations

1.6 Non‐Fundamental Vibrations

1.7 Predicting the Number of Fundamental Vibrations

1.8 The Force Constant

1.9 Some Theoretical Concepts

1.10 Basic Sample Preparation

1.10.1 Gaseous Samples

1.10.2 Non‐Volatile Liquids

1.10.3 Volatile Liquids

1.10.4 Solid Samples

1.11 Other Sampling Techniques

1.12 Some Suggestions and Comments on the Interpretation of Infrared Spectra

2. The Analysis of Infrared Spectra

2.1 Hydrocarbons (Straight Chain)

2.2 Hydrocarbons (Branched Chain)

2.3 Hydrocarbons (Cyclic)

2.4 Alkenes

2.5 Alkynes

2.6 Ethers (Alkyl-Alkyl)

2.7 Ethers (Aryl-Alkyl)

2.8 Aliphatic Halides

2.9 Amines

2.10 Ketones and Aldehydes

2.11 Alcohols

2.12 Organic Acids

2.13 Acid Halides

2.14 Amides

2.15 Esters

2.16 Lactones

2.17 Anhydrides

2.18 Nitriles

2.19 Aromatic Hydrocarbons

2.20 Salts of Carboxylic Acid

2.21 The Effects of Chelation on the Carbonyl Absorption

2.22 Phosphines, Phosphites, Phosphonates and Phosphates

2.23 Thioalcohols and Thiophenols

2.24 Silanes

2.25 Boranes

2.26 Sulfones, Sulfates, Sulfonic Acids (and Their Salts), Sulfites and Sulfoxides

2.26.1 Sulfones

2.26.2 Sulfates

2.26.3 Sulfonic Acids (and Their Salts)

2.26.4 Sulfites

2.26.5 Sulfoxides

3. Techniques, Innovations, and Applications in Infrared Spectroscopy

3.1 Advances in Infrared Spectroscopy

3.2 Fast Fourier Transform (FFT)

3.3 The Michelson Interferometer

3.4 The FTIR Microscope and Microsampling Techniques

3.5 Reflective Spectra

3.6 Specular or External Reflectance

3.7 Grazing Incidence Reflectance

3.8 Reflective-Absorption Spectra

3.9 Diffuse-Reflectance Spectra

3.10 Attenuated Total Reflectance (ATR)

3.11 Theory of the ATR Cell

3.12 Quantitative Infrared Analysis

3.13 Combined Thermogravimetric Analysis and FTIR (TG/FTIR)

3.14 The TG/FTIR Interface

3.15 GC/MS, GC/FTIR and GC/MS/FTIR

3.16 The GC/MS and GC/FTIR Interfaces

4. Problems in Infrared Spectroscopy

Suggested Readings and References

Appendix

A.1 Infrared Group Frequencies (cm ¹)

A.1.1 Infrared Solvents

A.1.2 Bands Related to Sample Preparation

A.2 General Infrared Assignments

A.3 Carbonyl Absorptions

A.3.1 Ketones (All Strong Absorptions)

A.3.2 α, β-Unsaturated, Cyclic Ketones (cm ¹)

A.3.3 Aldehydes (All Strong Absorptions)

A.3.4 Carboxylic Acids (All Strong Absorptions) (cm ¹)

A.3.5 Amides

A.3.5.1 Carbonyl Vibrations (Amide I Band, All Strong) (cm⁻¹)

A.3.5.2 N-H Stretching Vibration (All Medium)

A.3.6 N-H Deformation (Amide II Band, All Strong)

A.3.7 Esters Carbonyl (All Strong)

A.3.8 Anhydride Carbonyl (All Strong)

A.3.9 Hydrocarbon Chromophore

A.3.10 Substitution Patterns on Aromatic Ring (cm ¹)

A.3.11 C-C Multiple Bond Stretching (cm¹)

A.3.12 Acetylenic Types

A.3.13 Aromatic Skeletal-in-Plane Vibrations

A.4 Miscellaneous Compounds (Proximate Bands)

A.4.1 Alcohol and Phenols (Stretching) (cm ¹)

A.4.2 Amines, N-H Stretching

A.4.3 Unsaturated Nitr...

Table of contents

• Cover
• Halftitle
• Title
• Copyright
• Table of Contents