Preface ....................................................... vii
1 Introduction ................................................. 1
1.1 What is XAFS? ........................................... 1
1.2 Physics of XAFS ......................................... 2
1.3 Synchrotron radiation ................................... 4
1.4 Purpose of this book .................................... 6
2 Basic physics of X-ray absorption and scattering ............. 8
2.1 X-rays .................................................. 8
2.2 The structure of atoms .................................. 9
2.3 Atomic units ........................................... 11
2.4 Types of interactions .................................. 13
2.5 Cross sections ......................................... 14
2.6 Elastic scattering from free electrons ................. 20
2.7 Elastic scattering from electron distributions ......... 21
2.8 Elastic scattering from atoms with no excitation ....... 24
2.9 Elastic scattering from crystals ....................... 26
2.10 Fourier transform of the lattice ....................... 28
2.11 Compton scattering from free electrons ................. 32
2.12 Inelastic scattering from atoms ........................ 32
2.13 Core-hole lifetime ..................................... 33
3 Experimental ................................................ 36
3.1 Requirements for XAFS experiments ...................... 36
3.2 X-ray sources .......................................... 41
3.3 Synchrotron radiation .................................. 42
3.4 Beamlines and optics ................................... 52
3.5 X-ray detectors ........................................ 60
3.6 XAFS experiments ....................................... 80
3.7 Samples ................................................ 96
3.8 Data acquisition ...................................... 103
4 Theory ..................................................... 106
4.1 Introduction .......................................... 106
4.2 Transition rate ....................................... 107
4.3 Band structure, molecular orbital, clusters ........... 115
4.4 Multiple scattering expansion ......................... 118
4.5 Outline of theoretical calculation .................... 120
4.6 EXAFS equation ........................................ 125
5 Data analysis .............................................. 134
5.1 XANES ................................................. 135
5.2 EXAFS ................................................. 146
5.3 Data fitting .......................................... 173
6 Related techniques and conclusion .......................... 189
6.1 Related techniques .................................... 189
6.2 Conclusion ............................................ 191
Appendix 1 Introduction to Fourier transforms in EXAFS ....... 193
Appendix 2 Cumulants in EXAFS ................................ 212
Appendix 3 Optimizing X-ray filters .......................... 219
Appendix 4 Reference spectra ................................. 232
Appendix 5 X-ray tables ...................................... 241
References .................................................... 251
Index ......................................................... 258
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