Modern Raman Spectroscopy

Preface ix
Acknowledgements xi

1 Introduction, Basic Theory and Principles 1
1.1 Introduction 1
1.2 History 1
1.3 Basic Theory 2
1.4 Molecular Vibrations 7
1.5 Group Vibrations 10
1.6 Basic Interpretation of a Spectrum 11
1.7 Summary 17

2 Raman Instrumentation 19
2.1 Introduction 19
2.2 Choice of Instrument 19
2.3 Fibre Optic Coupling 26
2.4 Spatially Offset Raman Scattering and Transmission Raman Scattering 29
2.5 Raman Sample Presentation 30
2.6 Microscopy 41
2.7 Calibration 55
2.8 Summary 60

3 Data Presentation, Quantitation, Interpretation, Chemometrics and Machine Learning 63
3.1 Manipulation of Spectra 63
3.2 Presentation of Spectra 69
3.3 Quantitation 69
3.4 An Approach to Qualitative Interpretation 71
3.5 Chemometrics and Machine Learning 79
3.6 Spectra Formats for Transfer and Exchange of Data 83
3.7 Summary 84

4 The Theory of Raman Spectroscopy 85
4.1 Introduction 85
4.2 Absorption and Scattering 86
4.3 States of a System and Hooke's Law 88
4.4 The Basic Selection Rule 91
4.5 Number and Symmetry of Vibrations 92
4.6 The Mutual Exclusion Rule 93
4.7 Understanding Polarisability 94
4.8 Polarisability and the Measurement of Polarisation 98
4.9 Symmetry Elements and Point Groups 102
4.10 Isotopic Substitution 105
4.11 Lattice Modes 107
4.12 Summary 108

5 Resonance Raman Scattering 109
5.1 Introduction 109
5.2 The Basic Process 110
5.3 Key Differences Between Resonance and Normal Raman Scattering 111
5.4 Practical Aspects 120
5.5 Scope 123
5.6 Summary 125

6 Surface Enhanced Raman Scattering and Surface Enhanced Resonance Raman Scattering 127
6.1 Introduction 127
6.2 The Basic SERS Concept 129
6.3 Theory 131
6.4 Surface Chemistry 139
6.5 Wavelength Dependence 145
6.6 Surface Enhanced Resonance Raman Scattering (SERRS) 145
6.7 Quenching and Enhanced Fluorescence 146
6.8 Rules 146
6.9 Substrates 148
6.10 Quantitation and Detection 153
6.11 SESORS and SESORRS 157
6.12 Other Points 157

6.13 Summary 161

7 More Advanced Raman Scattering Techniques 163
7.1 Introduction 163
7.2 Instrument Advances and Other Methods 163
7.3 Non-linear Spectroscopies 165
7.4 Super Resolution Microscopy 172
7.5 Single-molecule Spectroscopy 173
7.6 Tip Enhanced Raman Scattering 174
7.7 Time Resolved Scattering 176
7.8 Fluorescence Rejection 177
7.9 Raman Optical Activity 180
7.10 UV Excitation 180
7.11 Summary 183

8 Specific Applications 185
8.1 Introduction 185
8.2 Single Elements and Inorganics 185
8.3 Gases and Vapours 192
8.4 Art, Archaeology and Forensic Applications 194
8.5 Colour Applications, Physical and Chemical Structure 201
8.6 Biological and Clinical Applications 207
8.7 Polymers and Emulsions 210
8.8 Materials and Electronic Applications 215
8.9 Summary 227

Appendix 1 Table of Inorganic Band Positions 235
Index 239