Core Level Spectroscopy of Solids Book

Preface xv Acknowledgments xvii Authors xix Chapter 1 Introduction 1 Chapter 2 Fundamental Aspects of Core Level Spectroscopies 11
2.1 Core Holes 11
2.1.1 Creation of Core Holes 11
2.1.2 Decay of Core Holes 12
2.2 Overview of Core Level Spectroscopies 14
2.2.1 Core Hole Spin-Orbit Splitting 14
2.2.2 Core Hole Excitation Spectroscopies 15
2.2.3 Core Hole Decay Spectroscopies 18
2.2.4 Resonant Photoelectron Processes 19
2.2.5 Resonant X-Ray Emission Channels 22
2.2.6 Overview of the RXES and NXES Transitions 23
2.3 Interaction of X-Rays with Matter 25
2.3.1 Electromagnetic Field 26
2.3.2 Transition to Quantum Mechanics 26
2.3.3 Interaction Hamiltonian 27
2.3.4 Golden Rule 27
2.4 Optical Transition Operators and X-Ray Absorption Spectra 28
2.4.1 Electric Dipole Transitions 29
2.4.2 Electric Quadrupole Transitions 29
2.4.3 Dipole Selection Rules 29
2.4.4 Transition Probabilities, Cross Sections, and Oscillator Strengths 30
2.4.5 Cross Section, Penetration Depth, and Excitation Frequency 31
2.4.6 X-Ray Attenuation Lengths 32
2.5 Interaction of Electrons with Matter 32
2.6 X-Ray Sources 34
2.6.1 Synchrotron Radiation Sources 34
2.6.2 X-Ray Beamlines and Monochromators 35
2.6.3 Other X-Ray Sources 36
2.7 Electron Sources 37 Chapter 3 Many-Body Charge-Transfer Effects in XPS and XAS 39
3.1 Introduction 39
3.2 Many-Body Charge-Transfer Effects in XPS 40
3.2.1 Basic Description of the XPS Process 40
3.3 General Expressions of Many-Body Effects 42
3.3.1 General Description 42
3.3.2 Generating Function and Dielectric Response 44
3.3.3 XPS Spectrum and Its Limiting Forms 45
3.3.3.1 SlowModulation Limit 47
3.3.3.2 Rapid Modulation Limit 47
3.4 General Effects in XPS Spectra 47
3.4.1 Screening by Free-Electron-Like Conduction Electrons 47
3.4.2 Screening by Lattice Relaxation Effects 49
3.4.3 Shake-Up Satellites 50
3.4.4 Lifetime Effects 50
3.4.4.1 Auger Transition 50
3.4.4.2 Radiative Transition 51
3.5 Typical Examples of XPS Spectra 52
3.5.1 Simple Metals 52
3.5.2 La Metal 56
3.5.2.1 Final State of Type (A) 59
3.5.2.2 Final State of Type (B) 60
3.5.3 Mixed Valence State in Ce Intermetallic Compounds 62
3.5.4 Insulating Mixed Valence Ce Compounds 67
3.5.5 Transition Metal Compounds 71
3.5.5.1 Model 71
3.5.5.2 Simplified Analysis 72
3.5.5.3 Case A: [Delta subscript f] > 0 ([Delta] > U[subscript dc]) 74
3.5.5.4 Case B: [Delta subscript f] [less than or equal] 0 ([Delta] [less than or equal] U[subscript dc]) 74
3.6 Many-Body Charge-Transfer Effects in XAS 76
3.6.1 General Expressions of Many-Body Effects 76
3.6.2 XAS in Simple Metals 76
3.6.3 XAS in La Metal 78
3.6.3.1 Case A: [epsilon subscript f] < [epsilon subscript F] 79
3.6.3.2 Case B: [epsilon subscript f] > [epsilon subscript F] 80
3.6.4 Ce 3d XAS of Mixed Valence Ce Compounds 81
3.6.5 Ce L[subscript 3] XAS 83
3.6.6 XAS in Transition Metal Compounds 87
3.7 Comparison of XPS and XAS 89 Chapter 4 Charge Transfer Multiplet Theory 93
4.1 Introduction 93
4.2 Atomic Multiplet Theory 95
4.2.1 Term Symbols 96
4.2.2 Some Simple Coupling Schemes 98
4.2.3 Term Symbols of d-Electrons 101
4.2.4 Matrix Elements 105
4.2.5 Energy Levels of Two d-Electrons 107
4.2.6 More Than Two Electrons 108
4.2.7 Matrix Elements of the 2p[superscript 3] Configuration 109
4.2.8 Hund's Rules 110
4.2.9 Final State Effects of Atomic Multiplets 111
4.3 Ligand Field Multiplet Theory 115
4.3.1 Ligand Field Multiplet Hamiltonian 116
4.3.2 Cubic Crystal Fields 117
4.3.3 Definitions of the Crystal Field Parameters 119
4.3.4 Energies of the 3d[superscript n] Configurations 120
4.3.5 Symmetry Effects in D[subscript 4h] Symmetry 124
4.3.6 Effect of the 3d Spin-Orbit Coupling 125
4.3.7 Consequences of Reduced Symmetry 126
4.3.8 3d[superscript 0] Systems in Octahedral Symmetry 126
4.3.9 Ab Initio LFM Calculations 132
4.4 Charge Transfer Multiplet Theory 133
4.4.1 Initial State Effects 134
4.4.2 Final State Effects 137
4.4.3 XAS Spectrum with Charge-Transfer Effects 138
4.4.4 Small Charge-Transfer Satellites in 2p XAS 140
4.4.5 Large Charge-Transfer Satellites in 2p XPS 141
4.4.5.1 3d[superscript 0] Compounds 142
4.4.5.2 3d[superscript 8] Compounds 143 Chapter 5 X-Ray Photoemission Spectroscopy 145
5.1 Introduction 145
5.2 Experimental Aspects 146
5.3 XPS of TM Compounds 146
5.3.1 2p XPS 146
5.3.2 Zaanen-Sawatzky-Allen Diagram 152
5.3.3 2p XPS in Early TM Systems 154
5.3.4 Effect of Multiplet Coupling on [Delta] and U[subscript dd] 158
5.3.5 3s XPS 160
5.3.6 3p XPS 164
5.4 XPS of RE Compounds 165
5.4.1 Simplified Analysis for RE Oxides 165
5.4.2 Application of Charge-Transfer Multiplet Theory 169
5.5 Resonant Photoemission Spectroscopy 176
5.5.1 Fundamental Aspects of RPES 177
5.5.2 RPES in Ni Metal and TM Compounds 180
5.5.2.1 3p RPES in Ni Metal 180
5.5.2.2 2p RPES in TM Compounds 182
5.5.2.3 3p RPES in NiO 185
5.5.3 3d and 4d RPES of Ce Compounds 185
5.5.4 Resonant XPS 187
5.5.5 Resonant Auger Electron Spectroscopy 188
5.5.6 Reducing the Lifetime Broadening in XAS 191
5.5.7 EQ and ED Excitations in the Pre-Edge of Ti 1s XAS of TiO[subscript 2] 191
5.6 Hard X-Ray Photoemission Spectroscopy 197
5.6.1 2p HAXPS of Cuprates 197
5.6.2 2p HAXPS of V[subscript 2]O[subscript 3] and La[subscript 1-x]Sr[subscript x]MnO[subscript 3] 198
5.6.3 Ce Compounds: Surface/Bulk Sensitivity 199
5.6.4 Resonant HAXPS of Ce Compounds 202
5.7 Resonant Inverse Photoemission Spectroscopy 205
5.8 Nonlocal Screening Effect in XPS 212
5.9 Auger Photoemission Coincidence Spectroscopy 218
5.10 Spin-Polarization and Magnetic Dichroism in XPS 221
5.10.1 Spin-Polarized Photoemission 221
5.10.2 Spin-Polarized Circular Dichroic Resonant Photoemission 221 Chapter 6 X-Ray Absorption Spectroscopy 225
6.1 Basics of X-Ray Absorption Spectroscopy 225
6.1.1 Metal L[subscript 2,3] Edges 228
6.2 Experimental Aspects 228
6.2.1 Transmission Detection 229
6.2.2 Energy Dispersive X-Ray Absorption 229
6.2.3 Fluorescence Yield 229
6.2.4 Self-Absorption Effects in Fluorescence Yield Detection 230
6.2.5 Nonlinear Decay Ratios and Distortions in Fluorescence Yield Spectra 230
6.2.6 Partial Fluorescence Yield 230
6.2.7 Electron Yield 231
6.2.8 Partial Electron Yield 231
6.2.9 Ion Yield 232
6.2.10 Detection of an EELS Spectrum 232
6.2.11 Low-Energy EELS Experiments 233
6.2.12 Space: X-Ray Spectromicroscopy and TEM-EELS 233
6.2.13 Time-Resolved X-Ray Absorption 234
6.2.14 Extreme Conditions 235
6.3 L[subscript 2,3] Edges of 3d TM Systems 235
6.3.1 3d[superscript 0] Systems 236
6.3.2 3d[superscript 1] Systems 237
6.3.2.1 VO[subscript 2] and LaTiO[subscript 3] 237
6.3.3 3d[superscript 2] Systems 237
6.3.4 3d[superscript 3] Systems 238
6.3.5 3d[superscript 4] Systems 239
6.3.5.1 LaMnO[subscript 3] 240
6.3.5.2 Mixed Spin Ground State in LiMnO[subscript 2] 240
6.3.6 3d[superscript 5] Systems 241
6.3.6.1 MnO 241
6.3.6.2 Fe[subscript 2]O[subscript 3] 242
6.3.6.3 Fe[superscript 3+](tacn)[subscript 2] 243
6.3.6.4 Fe[superscript 3+](CN)[subscript 6] 243
6.3.6.5 Intermediate Spin State of SrCoO[subscript 3] 244
6.3.7 3d[superscript 6] Systems 245
6.3.7.1 Effect of 3d Spin-Orbit Coupling in Fe[subscript 2]SiO[subscript 4] 246
6.3.7.2 Co[superscript 3+] Oxides 247
6.3.8 3d[superscript 7] Systems 248
6.3.8.1 Effects of 3d Spin-Orbit Coupling on the Ground State of Co[superscript 2+] 248
6.3.8.2 Mixed Spin Ground State in PrNiO[subscript 3] 249
6.3.9 3d[superscript 8] Systems 251
6.3.9.1 NiO 251
6.3.9.2 High-Spin and Low-Spin Ni[superscript 2+] and Cu[superscript 3+] Systems 251
6.3.10 3d[superscript 9] Systems 253
6.4 Other X-Ray Absorption Spectra of the 3d TM Systems 254
6.4.1 TM M[subscript 2,3] Edges 254
6.4.2 TM M[subscript 1] Edges 255
6.4.3 TM K Edges 255
6.4.4 Ligand K Edges 260
6.4.4.1 Oxygen K Edges of High T[subscript c] Copper Oxides 264
6.4.5 Soft X-Ray K Edges by X-Ray Raman Spectroscopy 264
6.4.5.1 Modifying the Selection Rules 265
6.5 X-Ray Absorption Spectra of the 4d and 5d TM Systems 265
6.5.1 L[subscript 2,3] Edges of 4d TM Systems 266
6.5.2 Picosecond Time-Resolved 2p XAS Spectra of [Ru(bpy) subscript 3 superscript 2+] 268
6.5.3 Higher Valent Ruthenium Compounds 269
6.5.4 Pd L Edges and the Number of 4d Holes in Pd Metal 270
6.5.5 X-Ray Absorption Spectra of the 5d Transition Metals 271
6.6 X-Ray Absorption Spectra of the 4f RE and 5f Actinide Systems 272
6.6.1 M[subscript 4,5] Edges of Rare Earths 273
6.6.1.1 M[subscript 4,5] Edge of Tm 274
6.6.1.2 M[subscript 4,5] Edge of La[superscript 3+] 277
6.6.1.3 M[subscript 4,5] Edge of CeO[subscript 2] 278
6.6.2 N[subscript 4,5] Edges of Rare Earths 278
6.6.3 L[subscript 2,3] Edges of Rare Earths 281
6.6.4 O[subscript 4,5] Edges of Actinides 282
6.6.5 M[subscript 4,5] Edges of Actinides 282 Chapter 7 X-Ray Magnetic Circular Dichroism 287
7.1 Introduction 287
7.2 XMCD Effects in the L[subscript 2,3] Edges of TM Ions and Compounds 288
7.2.1 Atomic Single Electron Model 288
7.2.2 XMCD Effects in Ni[superscript 2+] 293
7.2.3 XMCD of CrO[subscript 2] 297
7.2.4 Magnetic X-Ray Linear Dichroism 297
7.2.5 Orientation Dependence of XMCD and XMLD Effects 298
7.2.6 XMLD for Doped LaMnO[subscript 3] Systems 299
7.3 Sum Rules 299
7.3.1 Sum Rules for Orbital and Spin Moments 299
7.3.2 Application of the Sum Rules to Fe and Co Metals 302
7.3.3 Application of the Sum Rules to Au/Co-Nanocluster/Au Systems 304
7.3.4 Limitations of the Sum Rules 308
7.3.5 Theoretical Simulations of the Spin Sum Rule 309
7.4 XMCD Effects in the K Edges of Transition Metals 310
7.4.1 X-Ray Natural Circular Dichroism and X-Ray Optical Activity 311
7.5 XMCD Effects in the M Edges of Rare Earths 312
7.5.1 XMCD and XMLD Effects from Atomic Multiplets 312
7.5.2 Temperature Effects on the XMCD and XMLD 314
7.6 XMCD Effects in the L Edges of Rare Earth Systems 314
7.6.1 Effects of 4f5d Exchange Interaction 315
7.6.2 Contribution of Electric Quadrupole Transition 319
7.6.3 Effect of Hybridization between RE 5d and TM 3d States 319
7.6.4 XMCD at L Edges of R[subscript 2]Fe[subscript 14]B (R = La-Lu) 320
7.6.5 Mixed Valence Compound CeFe[subscript 2] 324
7.6.6 Multielectron Excitations 328
7.7 Applications of XMCD 329
7.7.1 Magnetic Oxides 329
7.7.2 Thin Magnetic (Multi)layers, Interface, and Surface Effects 330
7.7.3 Impurities, Adsorbates, and Metal Chains 332
7.7.4 Magnetic Nanoparticles and Catalyst Materials 333
7.7.5 Molecular Magnets 333
7.7.6 Metal Centers in Proteins 334 Chapter 8 Resonant X-Ray Emission Spectroscopy 335
8.1 Introduction 335
8.1.1 Experimental Aspects of XES (RXES and NXES) 337
8.1.1.1 Detectors for Soft X-Ray XES 338
8.1.1.2 Detectors for Hard X-Ray XES 338
8.1.1.3 X-Ray Raman Allows Soft X-Ray XAS under Extreme Conditions 338
8.1.2 Basic Description and Some Theoretical Aspects 338
8.2 Rare Earth Compounds 343
8.2.1 Effect of Intra-Atomic Multiplet Coupling 343
8.2.2 Effect of Interatomic Hybridization in CeO[subscript 2] and PrO[subscript 2] 348
8.2.3 Metallic Ce Compounds with Mixed-Valence Character 351
8.2.4 Kondo Resonance in Yb Compounds 354
8.2.5 Dy 2p3d RXES Detection of the 2p4f EQ Excitation 357
8.2.6 EQ Excitations in Light Rare Earth Elements 360
8.3 High T[subscript c] Cuprates and Related Materials 363
8.3.1 Cu 2p3d RXES 363
8.3.2 Cu 1s4p RXES 367
8.3.3 Cu 1s2p RXES 373
8.3.4 O 1s2p RXES 377
8.4 Nickel and Cobalt Compounds 380
8.4.1 Ni 2p3d RXES in NiO: Charge Transfer Excitations 380
8.4.2 Ni 2p3d RXES in NiO: dd Excitations 384
8.4.3 Ni 2p3d RXES in NiO: Spin-Flip Excitations 386
8.4.4 Ni 1s4p RXES of NiO: Pressure Dependence 387
8.4.5 Co 2p3d RXES in CoO and Other Co Compounds 389
8.4.6 Co 1s2p RXES of CoO: Effect of Resolution 389
8.4.7 Co 1s2p RXES: Nonlocal Dipole Transitions 391
8.5 Iron and Manganese Compounds 393
8.5.1 Fe 1s2p RXES of Iron Oxides: 2D RXES Images 393
8.5.2 HERFD-XAS of Iron Oxides 395
8.5.3 Fe 2p XAS Spectra Measured at the Fe K Edge 397
8.5.4 Valence Selective XAS 397
8.5.5 Mn 2p3d RXES of MnO 399
8.5.6 Mn 2p3d RXES: Interplay of dd and Charge Transfer Excitations 402
8.5.7 Mn 1s4p RXES of LaMnO[subscript 3] 405
8.5.8 Mn and Ni 1s3p XES: Chemical Sensitivity 406
8.5.9 Mn 1s3p XES: K Capture Versus X-Ray Ionization 408
8.5.9.1 Atomic Multiplet Calculation 409
8.5.9.2 LFM Calculation 410
8.5.9.3 Charge Transfer Multiplet Calculation 410
8.5.9.4 Coherent Calculation of Mn 1s3p NXES Spectra 411
8.6 Early Transition Metal Compounds 412
8.6.1 Ca 2p3s RXES in CaF[subscript 2] 413
8.6.2 Ti 2p3d RXES of TiO[subscript 2]: Polarization Dependence 415
8.6.3 Sc 2p3d RXES of the ScF[subscript 3], ScCl[subscript 3], and ScBr[subscript 3] 420
8.6.4 TM 2p3d RXES of d[superscript n] (n = 1, 2, 3) Systems 420
8.6.5 V 2p3d RXES of Vanadium Oxides 423
8.7 Electron Spin States Detected by RXES and NXES 423
8.7.1 Local Spin-Selective Excitation Spectra 423
8.7.2 Spin-Dependent TM 1s3p NXES Spectra 425
8.7.3 TM 1s3p NXES and Spin-Transitions 426
8.7.4 Local-Spin Selective XAS and XMCD 429
8.8 MCD in RXES of Ferromagnetic Systems 429
8.8.1 Longitudinal and Transverse Geometries in MCD-RXES 429
8.8.2 MCD-RXES in LG of CeFe[subscript 2] 433
8.8.3 Experiments and Theory of MCD-RXES in TG 435 Appendix A Precise Derivation of XPS Formula 439 Appendix B Derivation of Equation 3.88 in Chapter 3 443 Appendix C Fundamental Tensor Theory 447 Appendix D Derivation of the Orbital Moment Sum Rule 451 Appendix E Theoretical Test of the Spin Sum Rule 453 Appendix F Calculations of XAS Spectra with Single Electron Excitation Models 457 References 463 Index 483