List of Contributors xi
Preface xiii
1 Probing Actinide Bonds in the Gas Phase: Theory and Spectroscopy 1
Michael C. Heaven and Kirk A. Peterson
1.1 Introduction 1
1.2 Techniques for Obtaining Actinide?]Containing Molecules in the Gas Phase 2
1.3 Techniques for Spectroscopic Characterization of Gas?]Phase Actinide Compounds 5
1.3.1 Conventional Absorption and Emission Spectroscopy 5
1.3.2 Photoelectron Spectroscopy 6
1.3.3 Velocity Modulation and Frequency Comb Spectroscopy 6
1.3.4 LIF Spectroscopy 7
1.3.5 Two?]Photon Excitation Techniques 12
1.3.6 Anion Photodetachment Spectroscopy 15
1.3.7 Action Spectroscopy 17
1.3.8 Bond Energies and Reactivities from Mass Spectrometry 20
1.4 Considerations for Characterizing Actinide?]Containing Molecules in the Gas Phase by Ab Initio Methods 23
1.4.1 Electron Correlation Methods 24
1.4.2 Relativistic Effects 27
1.4.3 Basis Sets 29
1.5 Computational Strategies for Accurate Thermodynamics of Gas?]Phase Actinide Molecules 30
1.6 Ab Initio Molecular Spectroscopy of Gas?]Phase Actinide Compounds 34
1.6.1 Pure Rotational and Ro?]Vibrational Spectroscopy 34
1.6.2 Electronic Spectroscopy 37
1.7 Summary and Outlook 38
Acknowledgments 39
References 39
2 Speciation of Actinide Complexes, Clusters, and Nanostructures in Solution 53
Rami J. Batrice, Jennifer N. Wacker, and Karah E. Knope
2.1 Introduction 53
2.2 Potentiometry 54
2.2.1 Potentiometric Titrations to Reveal Speciation 54
2.2.2 Overview of Potentiometry in Aqueous Actinide Chemistry 59
2.3 Optical Spectroscopy 60
2.3.1 UV?]vis?]NIR Spectroscopy in Actinide Speciation 60
2.3.2 Fluorescence Spectroscopy 63
2.3.3 Overview of Optical Spectroscopy in Aqueous Actinide Speciation 68
2.4 NMR Spectroscopy 69
2.4.1 Probing Chemical Equilibria by NMR 69
2.4.2 Monitoring Product Formation/Evolution by NMR Spectroscopy 74
2.4.3 Monitoring Actinide Self?]Assembly by NMR Spectroscopy 75
2.4.4 Following Cluster Stability in Solution by NMR Spectroscopy 76
2.4.5 Overview of NMR Spectroscopy in Aqueous Actinide Chemistry 82
2.5 Raman Spectroscopy 82
2.5.1 Cluster Formation and Assembly 83
2.5.2 Spectral Deconvolution of Raman Data to Yield Speciation 85
2.5.3 Identifying the Nature of Cation-Cation Interactions in Solution 86
2.5.4 In the Absence of an "yl": Pa(V) Speciation in HF Solutions 89
2.5.5 Computational Assignment of Vibrational Spectra 92
2.5.6 Overview of Raman Spectroscopy 92
2.6 X?] ray Absorption Spectroscopy 93
2.6.1 EXAFS 94
2.6.2 Actinide Solution Speciation by EXAFS 95
2.6.3 EXAFS Structural Comparison of Complexes with Varying Oxidation States and Geometries 99
2.6.4 Overview of EXAFS 101
2.7 Small?] Angle X?]ray Scattering (SAXS) 102
2.7.1 Structure Elucidation by SAXS 102
2.7.2 SAXS Analysis of Cluster Evolution 104
2.7.3 Understanding Self?]Assembly Processes by SAXS 107
2.7.4 Overview of SAXS 110
2.8 High?] Energy X?]ray Scattering (HEXS) 110
2.8.1 Determining Coordination Number and Environment about a Metal Center 111
2.8.2 Deducing Metal-Ligand Coordination Modes 113
2.8.3 Following Oligomer Formation and Stability 116
2.8.4 Overview of HEXS 117
References 118
3 Complex Inorganic Actinide Materials 128
Matthew L. Marsh and Thomas E. Albrecht?]Schmitt
3.1 Introduction 128
3.2 Fluorides 129
3.2.1 Trivalent and Tetravalent Fluorides 129
3.2.2 Pentavalent and Hexavalent Fluorides 131
3.2.3 Fluoride Architectures 132
3.3 Borates 137
3.3.1 Functionalized Borates 138
3.3.2 Transuranic Borates 141
3.4 Sulfates 154
3.4.1 Thorium and Uranium 154
3.4.2 Transuranic Frameworks 162
3.5 Phosphates 167
3.6 Conclusion 176
References 176
4 Organometallic Actinide Complexes with Novel Oxidation States and Ligand Types 181
Trevor W. Hayton and Nikolas Kaltsoyannis
4.1 Introduction 181
4.2 Overview of Actinide Organometallic Chemistry 181
4.2.1 Overview of Thorium Organometallics 183
4.2.2 Overview of Uranium Organometallics 184
4.2.3 Overview of Transuranium Organometallics 184
4.3 Overview of Theoretical Methods 184
4.4 New Theoretical and Experimental Tools for Evaluating Covalency in the 5f Series 186
4.4.1 The Quantum Theory of Atoms?]in?]Molecules 186
4.4.2 Ligand K?]edge X?]ray Absorption Spectroscopy 187
4.4.3 Optical Spectroscopy 189
4.4.4 Nuclear Magnetic Resonance (NMR) Spectroscopy 191
4.4.5 Electrochemistry 192
4.5 Notable Discoveries in Actinide?]Carbon Chemistry 194
4.5.1 An(II) Complexes 195
4.5.2 ??]Acceptor Ligand Complexes 195
4.5.3 (Inverted) Arene Sandwich Complexes 198
4.5.4 Phosphorano?]Stabilized Carbene Complexes 199
4.5.5 Homoleptic Alkyl and Aryl Complexes 201
4.6 Single and Multiple Bonding between Uranium and Group 15 Elements 202
4.7 Complexes with Group 16 Donor Ligands 206
4.7.1 Terminal Mono?]oxo Complexes 206
4.7.2 Complexes with Heavy Chalcogen (S, Se, Te) Donors 207
4.8 Actinyl and Its Derivatives 210
4.8.1 Inverse Trans Influence (ITI) 211
4.8.2 Imido?]Substituted Analogues of Uranyl 212
4.8.3 Progress Toward the Isolation of a cis?]Uranyl Complex 216
4.9 Organoactinide Single?]Molecule Magnets 217
4.10 Future Work 219
Acknowledgments 220
References 220
5 Coordination of Actinides and the Chemistry Behind Solvent Extraction 237
Aurora E. Clark, Ping Yang, and Jenifer C. Shafer
5.1 Introduction 237
5.2 Overview of Separations Processes 238
5.2.1 Classic Processes - U/Pu Recovery 238
5.2.2 Advanced Separation Processes - Am/Cm Recovery 240
5.2.3 Aqueous?]Based Complexants for Trivalent An/Ln Separation 240
5.2.4 Recent Trends in Aqueous?]Based Trivalent An/Ln Separations 241
5.2.5 Separation of Hexavalent Actinides (SANHEX) Processes 241
5.3 Coordination and Speciation of Aqueous Actinides 243
5.3.1 Actinide Hydration 245
5.3.2 Cation-Cation Complexes in Separations Solution 247
5.3.3 Counterion Interactions with Aqueous Actinide Ions 248
5.3.4 Changes to Solvation and Speciation in Solvent Mixtures 249
5.4 Ligand Design 249
5.4.1 Solvating Extractants 250
5.4.2 Recent Trends in Solvating Extractants 251
5.4.3 Cation Exchange Reagents 253
5.4.4 Aqueous Complexants 254
5.4.5 Covalency and Ligand Design 255
5.4.6 Computational Screening of Separation Selectivity 257
5.5 Interfacial Chemistry of Solvent Extraction 258
5.5.1 Properties of the Interface and Its Characterization 259
5.5.2 Current Understanding of Interfacial Structure and Properties under Different Conditions 261
5.5.3 Synergism and Cooperative Phenomena at Interfaces 263
5.6 Concluding Remarks 266
Acronyms 267
Acknowledgments 269
References 269
6 Behaviour and Properties of Nuclear Fuels 283
Rudy Konings and Marjorie Bertolus
6.1 Introduction 283
6.2 UO2 284
6.2.1 Crystal Structure 284
6.2.2 Electronic Structure 285
6.2.3 Defect Chemistry 287
6.2.4 Transport Properties 290
6.2.4.1 Oxygen Diffusion 290
6.2.4.2 Uranium Diffusion 292
6.2.5 Thermophysical Properties 293
6.2.5.1 Phonon Kinetics 293
6.2.5.2 Thermal Expansion 294
6.2.5.3 Heat Capacity 296
6.2.5.4 Thermal Conductivity 297
6.2.6 Melting and the Liquid 299
6.3 Mixed Oxides 300
6.4 Nuclear Fuel Behaviour during Irradiation 304
6.4.1 Radiation Effects from Fission Fragments 305
6.4.2 Radiation Effects from Alpha Decay 306
6.4.3 Fission Product Behaviour 307
6.4.3.1 Fission Product Dissolution in the UO2 Matrix 308
6.4.3.2 Fission Product Diffusion, Coalescence' and Precipitation 309
6.4.3.3 Fission Gas Resolution 314
6.4.4 Helium Behaviour 314
6.4.5 Grain Boundary Effects 317
6.5 Concluding
Remarks 319
Acknowledgements 321
References 321
7 Ceramic Host Phases for Nuclear Waste Remediation 333
Gregory R. Lumpkin
7.1 Introduction 333
7.2 Types of Ceramic Nuclear Waste Forms 334
7.3 Radiation Damage Effects 336
7.3.1 Actinide Doping Experiments 337
7.3.2 Ion Irradiation Experiments 340
7.3.3 Natural Analogues 345
7.3.4 Atomistic Modeling 352
7.4 Performance in Aqueous Systems 358
7.4.1 Laboratory Experiments 358
7.4.2 Natural Systems 363
7.5 Summary and Conclusions 365
Acknowledgments 367
References 368
8 Sources and Behaviour of Actinide Elements in the Environment 378
M.A. Denecke, N. Bryan, S. Kalmykov, K. Morris, and F. Quinto
8.1 Introduction 378
8.2 Naturally Occurring Actinides 379
8.2.1 Commercial Uses of Naturally Occurring Actinides 381
8.2.2 Uranium Resources and Mining 381
8.2.3 Environmental Impacts of Uranium Mining and Milling 384
8.2.4 Thorium Resources and Potential Use as Fuel 387
8.3 Anthropogenic Actinides Release 387
8.3.1 Releases from Nuclear Reprocessing Facilities 388
8.3.2 Inventories of Releases from Accidents and Incidents 390
8.3.2.1 Source?]Dependent Speciation and Behaviour of Released Actinides 393
8.3.3 Burden from Nuclear Testing 395
8.3.3.1 Nuclear Testing 395
8.3.3.2 Actinides Released in Nuclear Testing 396
8.3.3.3 Debris and Fallout of Actinides from Atmospheric Nuclear Testing 398
8.3.3.4 Inventories of Actinides from Atmospheric Nuclear Testing 400
8.3.3.5 Environmental Behaviour of Fallout Actinides 402
8.4 Radionuclide Biogeochemistry - Contaminated Land and Radioactive Waste Disposal 404
8.4.1 Bioreduction Processes 405
8.4.2 Uranium Biogeochemistry 405
8.4.3 Technetium Biogeochemistry 408
8.4.4 Neptunium Biogeochemistry 409
8.4.5 Plutonium Biogeochemistry 409
8.5 Transport and Surface Complexation Modelling 410
8.5.1 Key Processes in Actinide Transport 410
8.5.2 Interactions of Actinides with Inorganic Phases 410
8.5.2.1 Examples of Actinide Interfacial Redox Behaviour 412
8.5.3 Surface Complexation Modelling 414
8.5.4 Incorporation 417
8.5.5 Humic Substances 418
8.5.6 Colloids 419
8.5.6.1 Intrinsic Colloids 420
8.5.6.2 Pseudo?]colloids 421
8.5.7 Damkohler Analysis of HS/Colloid?]Mediated Transport 421
8.6 Conclusions and Outlook 423
List of Acronyms 425
References 426
9 Actinide Biological Inorganic Chemistry: The Overlap of 5f Orbitals with Biology 445
Peter Agbo, Julian A. Rees, and Rebecca J. Abergel
9.1 Introduction 445
9.2 Interactions between Actinides and Living Systems 448
9.2.1 Uranium in a Geochemical Context 449
9.2.2 Uranium in Larger Mammalian Systems 452
9.2.3 Pentavalent Actinides Neptunium and Protactinium 452
9.2.4 Tetravalent Actinides Plutonium and Thorium 453
9.2.5 Trivalent Metals from Americium to Einsteinium 457
9.3 Molecular Interactions of Actinides with Biological Metal Transporters 458
9.3.1 Transferrin?]Mediated Metal Uptake Pathways 458
9.3.2 Ferric Ion Binding Proteins 460
9.3.3 Divalent Metal Ion Transport Pathways 462
9.3.4 Skeleton Deposition: The Role of the Bone Matrix 463
9.3.5 Small?]Molecule Metallophores 464
9.3.6 Siderophore Analogues for Chelation Therapy 467
9.4 Actinide Coordination for Radiopharmaceutical Applications 470
9.4.1 Common and Most Promising New Bifunctional Chelators for 225Ac and 227Th 472
9.4.2 Maximizing Radiometal Delivery and Minimizing Damage Through Chemistry 474
9.5 Approaching Actinide Biochemistry from a Theoretical Perspective 475
References 477
Index 490
