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Yin JF, Amidani L, Chen J, Li M, Xue B, Lai Y, Kvashnina K, Nyman M, Yin P. Spatiotemporal Studies of Soluble Inorganic Nanostructures with X-rays and Neutrons. Angew Chem Int Ed Engl 2024; 63:e202310953. [PMID: 37749062 DOI: 10.1002/anie.202310953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/23/2023] [Accepted: 09/25/2023] [Indexed: 09/27/2023]
Abstract
This Review addresses the use of X-ray and neutron scattering as well as X-ray absorption to describe how inorganic nanostructured materials assemble, evolve, and function in solution. We first provide an overview of techniques and instrumentation (both large user facilities and benchtop). We review recent studies of soluble inorganic nanostructure assembly, covering the disciplines of materials synthesis, processes in nature, nuclear materials, and the widely applicable fundamental processes of hydrophobic interactions and ion pairing. Reviewed studies cover size regimes and length scales ranging from sub-Ångström (coordination chemistry and ion pairing) to several nanometers (molecular clusters, i.e. polyoxometalates, polyoxocations, and metal-organic polyhedra), to the mesoscale (supramolecular assembly processes). Reviewed studies predominantly exploit 1) SAXS/WAXS/SANS (small- and wide-angle X-ray or neutron scattering), 2) PDF (pair-distribution function analysis of X-ray total scattering), and 3) XANES and EXAFS (X-ray absorption near-edge structure and extended X-ray absorption fine structure, respectively). While the scattering techniques provide structural information, X-ray absorption yields the oxidation state in addition to the local coordination. Our goal for this Review is to provide information and inspiration for the inorganic/materials science communities that may benefit from elucidating the role of solution speciation in natural and synthetic processes.
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Affiliation(s)
- Jia-Fu Yin
- State Key Laboratory of Luminescent Materials and Devices, South China Advanced Institute for Soft Matter Science and Technology, South China University of Technology, Guangzhou, 510640, China
| | - Lucia Amidani
- The Rossendorf Beamline at ESRF, The European Synchrotron, CS40220, 38043, Grenoble Cedex 9, France
- Institute of Resource Ecology, Helmholtz Zentrum Dresden-Rossendorf (HZDR) P.O. Box 510119, 01314, Dresden, Germany
| | - Jiadong Chen
- State Key Laboratory of Luminescent Materials and Devices, South China Advanced Institute for Soft Matter Science and Technology, South China University of Technology, Guangzhou, 510640, China
| | - Mu Li
- Institute of Advanced Science Facilities, Shenzhen, 518107, China
| | - Binghui Xue
- State Key Laboratory of Luminescent Materials and Devices, South China Advanced Institute for Soft Matter Science and Technology, South China University of Technology, Guangzhou, 510640, China
| | - Yuyan Lai
- State Key Laboratory of Luminescent Materials and Devices, South China Advanced Institute for Soft Matter Science and Technology, South China University of Technology, Guangzhou, 510640, China
| | - Kristina Kvashnina
- The Rossendorf Beamline at ESRF, The European Synchrotron, CS40220, 38043, Grenoble Cedex 9, France
- Institute of Resource Ecology, Helmholtz Zentrum Dresden-Rossendorf (HZDR) P.O. Box 510119, 01314, Dresden, Germany
| | - May Nyman
- Department of Chemistry, Oregon State University, Corvallis, OR, 97330, USA
| | - Panchao Yin
- State Key Laboratory of Luminescent Materials and Devices, South China Advanced Institute for Soft Matter Science and Technology, South China University of Technology, Guangzhou, 510640, China
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Chen JL, Blaha P, Kaltsoyannis N. DFT + U Simulation of the X-ray Absorption Near-Edge Structure of Bulk UO 2 and PuO 2. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2023; 127:17994-18000. [PMID: 37736292 PMCID: PMC10510436 DOI: 10.1021/acs.jpcc.3c03143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 07/25/2023] [Indexed: 09/23/2023]
Abstract
Hubbard U-corrected density functional theory within the periodic boundary condition model in the WIEN2k code is used to simulate the actinide LIII and O K edge X-ray absorption near-edge structure (XANES) for UO2 and PuO2. Spin-orbit coupling effects are included, as are possible excitonic effects using supercells with a core hole on one of the atoms. Our calculations yield spectra in excellent agreement with previous experiments and superior to previous simulations. Density of states analysis reveals the mechanism behind the XANES peaks: the main contribution to the U/Pu LIII edges comes from the U/Pu d states hybridized with O p states, while as expected, the O p states primarily determine the O K edges of both UO2 and PuO2. The O K edges also feature O p hybridizing with U/Pu d and f states in the low-energy region and with U/Pu s and p states for the higher-energy peaks.
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Affiliation(s)
- Jia-Li Chen
- Department
of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Peter Blaha
- Institute
of Materials Chemistry, TU Vienna, Vienna A-1060, Austria
| | - Nikolas Kaltsoyannis
- Department
of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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3
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Kobayashi T, Fushimi T, Mizukoshi H, Motokawa R, Sasaki T. Structural Approach to Understanding the Formation of Amorphous Metal Hydroxides. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:14656-14665. [PMID: 36399660 DOI: 10.1021/acs.langmuir.2c02081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
This study investigates the formation of amorphous tetravalent metal hydroxides, M(OH)4, based on the structural analysis by small- and wide-angle X-ray scattering (SWAXS) and on the electrical potential charge near the surface of M(OH)4 particles. The amorphous zirconium hydroxide solid phases that aged in NaCl and CaCl2 solutions at 25 °C exhibited a hierarchical structure consisting of primary particles of a few nanometers in size and their aggregates more than 100 nm in size. The SWAXS profiles suggested that the size of the primary particles depends on the ionic strength and electrolytes in the sample solutions. The smaller size of the primary particles observed in solutions with higher ionic strength can be explained by the thinner electrical double layer. Additionally, we focused on the ζ potentials of M(OH)4 suspensions in NaCl, NaNO3, and CaCl2 solutions. With the aid of reference systems of metal oxides, MO2, it was found that the ζ potentials were well interpreted by a traditional surface ionization and complexation model, and the size distributions of large aggregates were explained by the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory with the ζ potential values. The present study suggests the formation mechanism of amorphous metal hydroxides through a combination of structural analysis and investigation of electrical potentials.
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Affiliation(s)
- Taishi Kobayashi
- Department of Nuclear Engineering, Kyoto University, Kyotodaigaku-katsura, Nishikyo-ku, Kyoto615-8540, Japan
| | - Tomokazu Fushimi
- Department of Nuclear Engineering, Kyoto University, Kyotodaigaku-katsura, Nishikyo-ku, Kyoto615-8540, Japan
| | - Hirofumi Mizukoshi
- Department of Nuclear Engineering, Kyoto University, Kyotodaigaku-katsura, Nishikyo-ku, Kyoto615-8540, Japan
| | - Ryuhei Motokawa
- Materials Sciences Research Center, Japan Atomic Energy Agency (JAEA), Tokai, Naka-gun, Ibaraki319-1195, Japan
| | - Takayuki Sasaki
- Department of Nuclear Engineering, Kyoto University, Kyotodaigaku-katsura, Nishikyo-ku, Kyoto615-8540, Japan
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4
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Virot M, Dumas T, Cot-Auriol M, Moisy P, Nikitenko SI. Synthesis and multi-scale properties of PuO 2 nanoparticles: recent advances and open questions. NANOSCALE ADVANCES 2022; 4:4938-4971. [PMID: 36504736 PMCID: PMC9680947 DOI: 10.1039/d2na00306f] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 08/15/2022] [Indexed: 05/28/2023]
Abstract
Due to the increased attention given to actinide nanomaterials, the question of their structure-property relationship is on the spotlight of recent publications. Plutonium oxide (PuO2) particularly plays a central role in nuclear energetics and a comprehensive knowledge about its properties when nanosizing is of paramount interest to understand its behaviour in environmental migration schemes but also for the development of advanced nuclear energy systems underway. The element plutonium further stimulates the curiosity of scientists due to the unique physical and chemical properties it exhibits around the periodic table. PuO2 crystallizes in the fluorite structure of the face-centered cubic system for which the properties can be significantly affected when shrinking. Identifying the formation mechanism of PuO2 nanoparticles, their related atomic, electronic and crystalline structures, and their reactivity in addition to their nanoscale properties, appears to be a fascinating and challenging ongoing topic, whose recent advances are discussed in this review.
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Affiliation(s)
- Matthieu Virot
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM Marcoule France
| | - Thomas Dumas
- CEA, DEN, DMRC, Univ Montpellier Marcoule France
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Zhang X, Wang Z, Reimus P, Ma F, Soltanian MR, Xing B, Zang J, Wang Y, Dai Z. Plutonium reactive transport in fractured granite: Multi-species experiments and simulations. WATER RESEARCH 2022; 224:119068. [PMID: 36103780 DOI: 10.1016/j.watres.2022.119068] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 08/19/2022] [Accepted: 09/05/2022] [Indexed: 05/15/2023]
Abstract
Plutonium (Pu) in the subsurface environment can transport in different oxidation states as an aqueous solute or as colloidal particles. The transport behavior of Pu is affected by the relative abundances of these species and can be difficult to predict when they simultaneously exist. This study investigates the concurrent transport of Pu intrinsic colloids, Pu(IV)(aq) and Pu(V-VI)(aq) through a combination of controlled experiments and semi-analytical dual-porosity transport modeling. Pu transport experiments were conducted in a fractured granite at high and low flow rates to elucidate sorption processes and their scaling behavior. In the experiments, Pu(IV)(aq) was the least mobile of the Pu species, Pu(V-VI)(aq) had intermediate mobility, and the colloidal Pu, which consisted mainly of precipitated and/or hydrolyzed Pu(IV), was the most mobile. The semi-analytical modeling revealed that the sorption of each Pu species was rate-limited, as the sorption could not be described by assuming local equilibrium in the experiments. The model was able to describe the sorption of the different Pu species that occurring either on fracture surfaces, in the pores of the rock matrix, or simultaneously in both locations. While equally good fits to the data could be achieved using any of these assumptions, a fracture-dominated process was considered to be the most plausible because it provided the most reasonable estimates of sorption rate constants. Importantly, a key result of this work is that the sorption rate constant of all Pu species tends to decrease with increasing time scales, which implies that Pu will tend to be more mobile at longer time scales than observations at shorter time scales suggest. This result has important implications for predicting the environmental impacts of Pu in the safety assessments of geologic repositories for radioactive waste disposal, and we explore potential mechanistic bases for upscaling the sorption rate constants to time and distance scales that cannot be practically evaluated in experiments.
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Affiliation(s)
- Xiaoying Zhang
- Institute of Intelligent Simulation and Early Warning for Subsurface Environment, Jilin University, Changchun 130026, China; College of Construction Engineering, Jilin University, Changchun 130026, China
| | - Zheng Wang
- College of Construction Engineering, Jilin University, Changchun 130026, China
| | - Paul Reimus
- Los Alamos National Laboratory, Los Alamos, NM 87545, United States
| | - Funing Ma
- College of Construction Engineering, Jilin University, Changchun 130026, China
| | - Mohamad Reza Soltanian
- Departments of Geology and Environmental Engineering, University of Cincinnati, Cincinnati, OH, United States
| | - Baoshan Xing
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, United States
| | - Jianzheng Zang
- Institute of Nuclear and New Technology, Tsinghua University, Beijing 100084, China
| | - Yu Wang
- Institute of Nuclear and New Technology, Tsinghua University, Beijing 100084, China.
| | - Zhenxue Dai
- Institute of Intelligent Simulation and Early Warning for Subsurface Environment, Jilin University, Changchun 130026, China; College of Construction Engineering, Jilin University, Changchun 130026, China; Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Changchun 130026, China.
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6
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De Santis M, Sorbelli D, Vallet V, Gomes ASP, Storchi L, Belpassi L. Frozen-Density Embedding for Including Environmental Effects in the Dirac-Kohn-Sham Theory: An Implementation Based on Density Fitting and Prototyping Techniques. J Chem Theory Comput 2022; 18:5992-6009. [PMID: 36172757 PMCID: PMC9558305 DOI: 10.1021/acs.jctc.2c00499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Frozen density embedding (FDE) represents an embedding scheme in which environmental effects are included from first-principles calculations by considering the surrounding system explicitly by means of its electron density. In the present paper, we extend the full four-component relativistic Dirac-Kohn-Sham (DKS) method, as implemented in the BERTHA code, to include environmental and confinement effects with the FDE scheme (DKS-in-DFT FDE). The implementation, based on the auxiliary density fitting techniques, has been enormously facilitated by BERTHA's python API (PyBERTHA), which facilitates the interoperability with other FDE implementations available through the PyADF framework. The accuracy and numerical stability of this new implementation, also using different auxiliary fitting basis sets, has been demonstrated on the simple NH3-H2O system, in comparison with a reference nonrelativistic implementation. The computational performance has been evaluated on a series of gold clusters (Aun, with n = 2, 4, 8) embedded into an increasing number of water molecules (5, 10, 20, 40, and 80 water molecules). We found that the procedure scales approximately linearly both with the size of the frozen surrounding environment (consistent with the underpinnings of the FDE approach) and with the size of the active system (in line with the use of density fitting). Finally, we applied the code to a series of heavy (Rn) and super-heavy elements (Cn, Fl, Og) embedded in a C60 cage to explore the confinement effect induced by C60 on their electronic structure. We compare the results from our simulations, with respect to more-approximate models employed in the atomic physics literature. Our results indicate that the specific interactions described by FDE are able to improve upon the cruder approximations currently employed, and, thus, they provide a basis from which to generate more-realistic radial potentials for confined atoms.
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Affiliation(s)
- Matteo De Santis
- Univ. Lille, CNRS, UMR 8523-PhLAM-Physique des Lasers Atomes et Molécules, F-59000 Lille, France
| | - Diego Sorbelli
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy.,Istituto di Scienze e Tecnologie Chimiche (SCITEC), Consiglio Nazionale delle Ricerche c/o Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy
| | - Valérie Vallet
- Univ. Lille, CNRS, UMR 8523-PhLAM-Physique des Lasers Atomes et Molécules, F-59000 Lille, France
| | | | - Loriano Storchi
- Istituto di Scienze e Tecnologie Chimiche (SCITEC), Consiglio Nazionale delle Ricerche c/o Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy.,Dipartimento di Farmacia, Università degli Studi 'G. D'Annunzio', Via dei Vestini 31, 66100 Chieti, Italy
| | - Leonardo Belpassi
- Istituto di Scienze e Tecnologie Chimiche (SCITEC), Consiglio Nazionale delle Ricerche c/o Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy
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7
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Gerber E, Romanchuk AY, Weiss S, Kuzenkova A, Hunault MOJY, Bauters S, Egorov A, Butorin SM, Kalmykov SN, Kvashnina KO. To form or not to form: PuO 2 nanoparticles at acidic pH. ENVIRONMENTAL SCIENCE. NANO 2022; 9:1509-1518. [PMID: 35520632 PMCID: PMC9009106 DOI: 10.1039/d1en00666e] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 02/08/2022] [Indexed: 11/25/2022]
Abstract
The aim of this study is to synthesize PuO2 nanoparticles (NPs) at low pH values and characterize the materials using laboratory and synchrotron-based methods. Properties of the PuO2 NPs formed under acidic conditions (pH 1-4) are explored here at the atomic scale. High-resolution transmission electron microscopy (HRTEM) is applied to characterize the crystallinity, morphology and size of the particles. It is found that 2 nm crystalline NPs are formed with a PuO2 crystal structure. High energy resolution fluorescence detected (HERFD) X-ray absorption spectroscopy at the Pu M4 edge has been used to identify the Pu oxidation states and recorded data are analysed using the theory based on the Anderson impurity model (AIM). The experimental data obtained on NPs show that the Pu(iv) oxidation state dominates in all NPs formed at pH 1-4. However, the suspension at pH 1 demonstrates the presence of Pu(iii) and Pu(vi) in addition to the Pu(iv), which is associated with redox dissolution of PuO2 NPs under acidic conditions. We discuss in detail the mechanism that affects the PuO2 NPs synthesis under acidic conditions and compare it with one in neutral and alkaline conditions. Hence, the results shown here, together with the first Pu M4 HERFD data on PuF3 and PuF4 compounds, are significant for the colloid facilitated transport governing the migration of plutonium in a subsurface environment.
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Affiliation(s)
- Evgeny Gerber
- Lomonosov Moscow State University, Department of Chemistry 119991 Moscow Russia
- The Rossendorf Beamline at ESRF - The European Synchrotron CS40220 38043 Grenoble Cedex 9 France
- Helmholtz Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology PO Box 510119 01314 Dresden Germany
| | - Anna Yu Romanchuk
- Lomonosov Moscow State University, Department of Chemistry 119991 Moscow Russia
| | - Stephan Weiss
- Helmholtz Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology PO Box 510119 01314 Dresden Germany
| | | | | | - Stephen Bauters
- The Rossendorf Beamline at ESRF - The European Synchrotron CS40220 38043 Grenoble Cedex 9 France
- Helmholtz Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology PO Box 510119 01314 Dresden Germany
| | - Alexander Egorov
- Lomonosov Moscow State University, Department of Chemistry 119991 Moscow Russia
| | - Sergei M Butorin
- Condensed Matter Physics of Energy Materials, X-ray Photon Science, Department of Physics and Astronomy, Uppsala University P.O. Box 516 SE-751 20 Uppsala Uppsala Sweden
| | - Stepan N Kalmykov
- Lomonosov Moscow State University, Department of Chemistry 119991 Moscow Russia
| | - Kristina O Kvashnina
- Lomonosov Moscow State University, Department of Chemistry 119991 Moscow Russia
- The Rossendorf Beamline at ESRF - The European Synchrotron CS40220 38043 Grenoble Cedex 9 France
- Helmholtz Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology PO Box 510119 01314 Dresden Germany
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8
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Romanchuk A, Trigub A, Plakhova T, Kuzenkova A, Svetogorov R, Kvashnina K, Kalmykov S. Effective coordination numbers from EXAFS: general approaches for lanthanide and actinide dioxides. JOURNAL OF SYNCHROTRON RADIATION 2022; 29:288-294. [PMID: 35254290 PMCID: PMC8900841 DOI: 10.1107/s160057752101300x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/07/2021] [Indexed: 06/01/2023]
Abstract
Extended X-ray absorption fine structure (EXAFS) is a comprehensive and usable method for characterizing the structures of various materials, including radioactive and nuclear materials. Unceasing discussions about the interpretation of EXAFS results for actinide nanoparticles (NPs) or colloids were still present during the last decade. In this study, new experimental data for PuO2 and CeO2 NPs with different average sizes were compared with published data on AnO2 NPs that highlight the best fit and interpretation of the structural data. In terms of the structure, PuO2, CeO2, ThO2, and UO2 NPs exhibit similar behaviors. Only ThO2 NPs have a more disordered and even partly amorphous structure, which results in EXAFS characteristics. The proposed new core-shell model for NPs with calculated effective coordination number perfectly fits the results of the variations in a metal-metal shell with a decrease in NP size.
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Affiliation(s)
- Anna Romanchuk
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, Bld. 3, Moscow 119991, Russian Federation
| | - Alexander Trigub
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, Bld. 3, Moscow 119991, Russian Federation
- National Research Centre ‘Kurchatov Institute’, Pl. Kurchatova 1, Moscow 123182, Russian Federation
| | - Tatiana Plakhova
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, Bld. 3, Moscow 119991, Russian Federation
| | - Anastasiia Kuzenkova
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, Bld. 3, Moscow 119991, Russian Federation
| | - Roman Svetogorov
- National Research Centre ‘Kurchatov Institute’, Pl. Kurchatova 1, Moscow 123182, Russian Federation
| | - Kristina Kvashnina
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, Bld. 3, Moscow 119991, Russian Federation
- The Rossendorf Beamline at ESRF – The European Synchrotron, CS40220, 38043 Grenoble Cedex 9, France
- Institute of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), PO Box 510119, 01314 Dresden, Germany
| | - Stepan Kalmykov
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, Bld. 3, Moscow 119991, Russian Federation
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9
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Schacherl B, Joseph C, Lavrova P, Beck A, Reitz C, Prüssmann T, Fellhauer D, Lee JY, Dardenne K, Rothe J, Geckeis H, Vitova T. Paving the way for examination of coupled redox/solid-liquid interface reactions: 1 ppm Np adsorbed on clay studied by Np M5-edge HR-XANES spectroscopy. Anal Chim Acta 2022; 1202:339636. [DOI: 10.1016/j.aca.2022.339636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 02/06/2022] [Accepted: 02/17/2022] [Indexed: 11/01/2022]
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10
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Sergentu DC, Autschbach J. X-ray absorption spectra of f-element complexes: insight from relativistic multiconfigurational wavefunction theory. Dalton Trans 2022; 51:1754-1764. [PMID: 35022645 DOI: 10.1039/d1dt04075h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
X-ray absorption near edge structure (XANES) spectroscopy, coupled with ab initio calculations, has emerged as the state-of-the-art tool for elucidating the metal-ligand bonding in f-element complexes. This highlight presents recent efforts in calculating XANES spectra of lanthanide and actinide compounds with relativistic multiconfiguration wavefunction approaches that account for differences in donation bonding in the ground state (GS) versus a core-excited state (ES), multiplet effects, and spin-orbit-coupling. With the GS and ES wavefunctions available, including spin-orbit effects, an arsenal of chemical bonding tools that are popular among chemists can be applied to rationalize the observed intensities in terms of covalent bonding.
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Affiliation(s)
- Dumitru-Claudiu Sergentu
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, NY 14260-3000, USA.
| | - Jochen Autschbach
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, NY 14260-3000, USA.
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11
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Kvashnina KO, Butorin SM. High-energy resolution X-ray spectroscopy at actinide M 4,5 and ligand K edges: what we know, what we want to know, and what we can know. Chem Commun (Camb) 2022; 58:327-342. [PMID: 34874022 PMCID: PMC8725612 DOI: 10.1039/d1cc04851a] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 11/15/2021] [Indexed: 12/20/2022]
Abstract
In recent years, scientists have progressively recognized the role of electronic structures in the characterization of chemical properties for actinide containing materials. High-energy resolution X-ray spectroscopy at the actinide M4,5 edges emerged as a promising direction because this method can probe actinide properties at the atomic level through the possibility of reducing the experimental spectral width below the natural core-hole lifetime broadening. Parallel to the technical developments of the X-ray method and experimental discoveries, theoretical models, describing the observed electronic structure phenomena, have also advanced. In this feature article, we describe the latest progress in the field of high-energy resolution X-ray spectroscopy at the actinide M4,5 and ligand K edges and we show that the methods are able to (a) provide fingerprint information on the actinide oxidation state and ground state characters (b) probe 5f occupancy, non-stoichiometry, defects, and ligand/metal ratio and (c) investigate the local symmetry and effects of the crystal field. We discuss the chemical aspects of the electronic structure in terms familiar to chemists and materials scientists and conclude with a brief description of new opportunities and approaches to improve the experimental methodology and theoretical analysis for f-electron systems.
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Affiliation(s)
- Kristina O Kvashnina
- The Rossendorf Beamline at ESRF, The European Synchrotron, CS40220, 38043 Grenoble Cedex 9, France.
- Institute of Resource Ecology, Helmholtz Zentrum Dresden-Rossendorf (HZDR), PO Box 510119, 01314 Dresden, Germany
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Sergei M Butorin
- Condensed Matter Physics of Energy Materials, X-ray Photon Science, Department of Physics and Astronomy, Uppsala University, P.O. Box 516, SE-751 20 Uppsala, Sweden.
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12
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Schacherl B, Prüssmann T, Dardenne K, Hardock K, Krepper V, Rothe J, Vitova T, Geckeis H. Implementation of cryogenic tender X-ray HR-XANES spectroscopy at the ACT station of the CAT-ACT beamline at the KIT Light Source. JOURNAL OF SYNCHROTRON RADIATION 2022; 29:80-88. [PMID: 34985425 PMCID: PMC8733978 DOI: 10.1107/s1600577521012650] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 11/28/2021] [Indexed: 06/07/2023]
Abstract
The ACT experimental station of the CAT-ACT wiggler beamline at the Karlsruhe Institute of Technology (KIT) Light Source is dedicated to the investigation of radionuclide materials with radioactivities up to 1000000 times the exemption limit by various speciation techniques applying monochromatic X-rays. In this article, the latest technological developments at the ACT station that enable high-resolution X-ray absorption near-edge structure (HR-XANES) spectroscopy for low radionuclide loading samples are highlighted - encompassing the investigation of actinide elements down to 1 p.p.m. concentration - combined with a cryogenic sample environment reducing beam-induced sample alterations. One important part of this development is a versatile gas tight plexiglass encasement ensuring that all beam paths in the five-analyzer-crystal Johann-type X-ray emission spectrometer run within He atmosphere. The setup enables the easy exchange between different experiments (conventional X-ray absorption fine structure, HR-XANES, high-energy or wide-angle X-ray scattering, tender to hard X-ray spectroscopy) and opens up the possibility for the investigation of environmental samples, such as specimens containing transuranium elements from contaminated land sites or samples from sorption and diffusion experiments to mimic the far field of a breached nuclear waste repository.
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Affiliation(s)
- Bianca Schacherl
- Institute for Nuclear Waste Disposal (INE), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Tim Prüssmann
- Institute for Nuclear Waste Disposal (INE), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Kathy Dardenne
- Institute for Nuclear Waste Disposal (INE), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Kirsten Hardock
- Institute for Nuclear Waste Disposal (INE), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Volker Krepper
- Institute for Nuclear Waste Disposal (INE), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Jörg Rothe
- Institute for Nuclear Waste Disposal (INE), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Tonya Vitova
- Institute for Nuclear Waste Disposal (INE), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Horst Geckeis
- Institute for Nuclear Waste Disposal (INE), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
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13
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Dumas T, Virot M, Menut D, Tamain C, Micheau C, Dourdain S, Diat O. Size and structure of hexanuclear plutonium oxo-hydroxo clusters in aqueous solution from synchrotron analysis. JOURNAL OF SYNCHROTRON RADIATION 2022; 29:30-36. [PMID: 34985420 PMCID: PMC8733971 DOI: 10.1107/s1600577521012005] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 11/10/2021] [Indexed: 06/01/2023]
Abstract
The size and shape of a water-soluble hexanuclear plutonium cluster were probed by combining synchrotron small-angle X-ray scattering (SAXS) and extended X-ray absorption fine structure (EXAFS). A specific setup coupling both techniques and dedicated to radioactive samples on the MARS beamline endstation at Synchrotron SOLEIL is described. The plutonium hexanuclear cores are well stabilized by the 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid ligands and this allows a good evaluation of the setup to probe the very small plutonium core. The results show that, in spite of the constrained conditions required to avoid any risk of sample dispersion, the flux and the sample environment are optimized to obtain a very good signal-to-noise ratio, allowing the detection of small plutonium aggregates in an aqueous phase. The structure of the well defined hexanuclear cluster has been confirmed by EXAFS measurements in solution and correlated with SAXS data processing and modelling. An iterative comparison of classical fit models (Guinier or sphere form factor) with the experimental results allowed a better interpretation of the SAXS signal that will be relevant for future work under environmentally relevant conditions.
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Affiliation(s)
- Thomas Dumas
- CEA, DES, ISEC, DMRC, Univ Montpellier, Marcoule, France
| | - Matthieu Virot
- ICSM, CEA, Univ Montpellier, CNRS, ENSCM, Bagnols sur Cèze, France
| | - Denis Menut
- Synchrotron SOLEIL, L’Orme des Merisiers Saint Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France
| | | | - Cyril Micheau
- ICSM, CEA, Univ Montpellier, CNRS, ENSCM, Bagnols sur Cèze, France
| | | | - Olivier Diat
- ICSM, CEA, Univ Montpellier, CNRS, ENSCM, Bagnols sur Cèze, France
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14
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Sergentu DC, Autschbach J. Covalency in Actinide(IV) Hexachlorides in Relation to Chlorine K-Edge X-ray Absorption Structure. Chem Sci 2022; 13:3194-3207. [PMID: 35414875 PMCID: PMC8926251 DOI: 10.1039/d1sc06454a] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 02/03/2022] [Indexed: 12/02/2022] Open
Abstract
Chlorine K-edge X-ray absorption near edge structure (XANES) in actinideIV hexachlorides, [AnCl6]2− (An = Th–Pu), is calculated with relativistic multiconfiguration wavefunction theory (WFT). Of particular focus is a 3-peak feature emerging from U toward Pu, and its assignment in terms of donation bonding to the An 5f vs. 6d shells. With or without spin–orbit coupling, the calculated and previously measured XANES spectra are in excellent agreement with respect to relative peak positions, relative peak intensities, and peak assignments. Metal–ligand bonding analyses from WFT and Kohn–Sham theory (KST) predict comparable An 5f and 6d covalency from U to Np and Pu. Although some frontier molecular orbitals in the KST calculations display increasing An 5f–Cl 3p mixing from Th to Pu, because of energetic stabilization of 5f relative to the Cl 3p combinations of the matching symmetry, increasing hybridization is neither seen in the WFT natural orbitals, nor is it reflected in the calculated bond orders. The appearance of the pre-edge peaks from U to Pu and their relative intensities are rationalized simply by the energetic separation of transitions to 6d t2gversus transitions to weakly-bonded and strongly stabilized a2u, t2u and t1u orbitals with 5f character. The study highlights potential pitfalls when interpreting XANES spectra based on ground state Kohn–Sham molecular orbitals. Chlorine K-edge XANES of An(iv) hexachlorides, calculated with multiconfiguration wavefunction theory, is interpreted in terms of similar metal–ligand covalency along the An = Th–Pu series.![]()
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Affiliation(s)
- Dumitru-Claudiu Sergentu
- Department of Chemistry, University at Buffalo State University of New York Buffalo NY 14260-3000 USA
| | - Jochen Autschbach
- Department of Chemistry, University at Buffalo State University of New York Buffalo NY 14260-3000 USA
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15
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Amidani L, Retegan M, Volkova A, Popa K, Martin PM, Kvashnina KO. Probing the Local Coordination of Hexavalent Uranium and the Splitting of 5f Orbitals Induced by Chemical Bonding. Inorg Chem 2021; 60:16286-16293. [PMID: 34677932 DOI: 10.1021/acs.inorgchem.1c02107] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report here a detailed experimental and theoretical investigation of hexavalent uranium in various local configurations with a high-energy-resolution fluorescence-detected X-ray absorption near-edge structure at the U M4 edge. We show the pronounced sensitivity of the technique to the arrangement of atoms around the absorber and provide a detailed theoretical interpretation revealing the nature of spectral features. Calculations based on density functional theory and on crystal field multiplet theory indicate that for all local configurations analyzed, the main peak corresponds to nonbonding 5f orbitals, and the highest energy peak corresponds to antibonding 5f orbitals. Our findings agree with the accepted interpretation of uranyl spectral features and embed the latter in a broader field of view, which interprets the spectra of a large variety of U6+-containing samples on a common theoretical ground.
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Affiliation(s)
- Lucia Amidani
- The Rossendorf Beamline at ESRF, The European Synchrotron, 38043 Grenoble Cedex 9, France.,Institute of Resource Ecology, Helmholtz Zentrum Dresden-Rossendorf (HZDR), P.O. Box 510119, 01314 Dresden, Germany
| | - Marius Retegan
- ESRF-The European Synchrotron, 38043 Grenoble Cedex 9, France
| | - Anna Volkova
- Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Karin Popa
- European Commission, Joint Research Centre, Nuclear Safety and Security Directorate, Karlsruhe 76344, Germany
| | - Philippe M Martin
- CEA, DES, ISEC, DMRC, University of Montpellier, Marcoule, 30207 Bagnols sur Cèze, France
| | - Kristina O Kvashnina
- The Rossendorf Beamline at ESRF, The European Synchrotron, 38043 Grenoble Cedex 9, France.,Institute of Resource Ecology, Helmholtz Zentrum Dresden-Rossendorf (HZDR), P.O. Box 510119, 01314 Dresden, Germany.,Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia
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16
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Estevenon P, Dumas T, Solari PL, Welcomme E, Szenknect S, Mesbah A, Kvashnina KO, Moisy P, Poinssot C, Dacheux N. Formation of plutonium(IV) silicate species in very alkaline reactive media. Dalton Trans 2021; 50:12528-12536. [PMID: 34545888 DOI: 10.1039/d1dt02248b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Studying the speciation of Pu(IV) in very alkaline and silicate ion rich reactive media allowed identification of the formation of plutonium(IV)-silicate colloidal suspensions which were stable for months. These colloids were stabilized in aqueous solution for pH > 13 and for concentrations around 10-2 mol L-1. Successive filtration processes allowed evaluation of their size, which was found to be smaller than 6 nm. Their structural characterization by XAS evidenced that their structure was similar to those identified for the other tetravalent actinide-silicate colloidal systems like thorium, uranium and neptunium. Their formation could explain the increase of plutonium solubility usually observed in alkaline silicate-rich solutions and could affect the plutonium mobility as a result in contaminated sites or in other environmental permeable media.
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Affiliation(s)
- Paul Estevenon
- CEA, DES, ISEC, DMRC, Univ Montpellier, Marcoule, France. .,ICSM, Univ Montpellier, CNRS, CEA, ENSCM, Bagnols-sur-Cèze, France. .,The Rossendorf Beamline at the ESRF, CS40220, 38043 Grenoble Cedex 9, France.,Helmholtz Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology, P.O. Box 510119, 01314, Dresden, Germany
| | - Thomas Dumas
- CEA, DES, ISEC, DMRC, Univ Montpellier, Marcoule, France.
| | - Pier Lorenzo Solari
- Synchrotron Soleil, L'Orme des Merisiers, Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex, France
| | | | | | - Adel Mesbah
- ICSM, Univ Montpellier, CNRS, CEA, ENSCM, Bagnols-sur-Cèze, France.
| | - Kristina O Kvashnina
- The Rossendorf Beamline at the ESRF, CS40220, 38043 Grenoble Cedex 9, France.,Helmholtz Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology, P.O. Box 510119, 01314, Dresden, Germany
| | - Philippe Moisy
- CEA, DES, ISEC, DMRC, Univ Montpellier, Marcoule, France.
| | | | - Nicolas Dacheux
- ICSM, Univ Montpellier, CNRS, CEA, ENSCM, Bagnols-sur-Cèze, France.
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17
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Corbey JF, Sweet LE, Sinkov SI, Reilly DD, Parker CM, Lonergan JM, Johnson TJ. Quantitative Microstructural Characterization of Plutonium Oxalate Auto‐Degradation and Evidence for PuO
2
Nanocrystal Formation. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100511] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jordan F. Corbey
- Pacific Northwest National Laboratory 902 Battelle Boulevard Richland, WA 99352 USA
| | - Lucas E. Sweet
- Pacific Northwest National Laboratory 902 Battelle Boulevard Richland, WA 99352 USA
| | - Sergey I. Sinkov
- Pacific Northwest National Laboratory 902 Battelle Boulevard Richland, WA 99352 USA
| | - Dallas D. Reilly
- Pacific Northwest National Laboratory 902 Battelle Boulevard Richland, WA 99352 USA
| | - Cyrena M. Parker
- Pacific Northwest National Laboratory 902 Battelle Boulevard Richland, WA 99352 USA
| | - Jason M. Lonergan
- Pacific Northwest National Laboratory 902 Battelle Boulevard Richland, WA 99352 USA
| | - Timothy J. Johnson
- Pacific Northwest National Laboratory 902 Battelle Boulevard Richland, WA 99352 USA
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18
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Amidani L, Vaughan GBM, Plakhova TV, Romanchuk AY, Gerber E, Svetogorov R, Weiss S, Joly Y, Kalmykov SN, Kvashnina KO. The Application of HEXS and HERFD XANES for Accurate Structural Characterisation of Actinide Nanomaterials: The Case of ThO 2. Chemistry 2021; 27:252-263. [PMID: 32956492 PMCID: PMC7839789 DOI: 10.1002/chem.202003360] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/07/2020] [Indexed: 11/22/2022]
Abstract
The structural characterisation of actinide nanoparticles (NPs) is of primary importance and hard to achieve, especially for non-homogeneous samples with NPs less than 3 nm. By combining high-energy X-ray scattering (HEXS) and high-energy-resolution fluorescence-detected X-ray absorption near-edge structure (HERFD XANES) analysis, we have characterised for the first time both the short- and medium-range order of ThO2 NPs obtained by chemical precipitation. By using this methodology, a novel insight into the structures of NPs at different stages of their formation has been achieved. The pair distribution function revealed a high concentration of ThO2 small units similar to thorium hexamer clusters mixed with 1 nm ThO2 NPs in the initial steps of formation. Drying the precipitates at around 150 °C promoted the recrystallisation of the smallest units into more thermodynamically stable ThO2 NPs. HERFD XANES analysis at the thorium M4 edge, a direct probe for f states, showed variations that we have correlated with the breakdown of the local symmetry around the thorium atoms, which most likely concerns surface atoms. Together, HEXS and HERFD XANES are a powerful methodology for investigating actinide NPs and their formation mechanism.
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Affiliation(s)
- Lucia Amidani
- The Rossendorf Beamline at ESRFThe European SynchrotronCS4022038043Grenoble Cedex 9France
- Institute of Resource EcologyHelmholtz Zentrum Dresden-Rossendorf (HZDR), PO Box 51011901314DresdenGermany
| | | | | | - Anna Yu. Romanchuk
- Department of ChemistryLomonosov Moscow State University119991MoscowRussia
| | - Evgeny Gerber
- The Rossendorf Beamline at ESRFThe European SynchrotronCS4022038043Grenoble Cedex 9France
- Department of ChemistryLomonosov Moscow State University119991MoscowRussia
| | - Roman Svetogorov
- National Research Centre “Kurchatov Institute”123182MoscowRussia
| | - Stephan Weiss
- Institute of Resource EcologyHelmholtz Zentrum Dresden-Rossendorf (HZDR), PO Box 51011901314DresdenGermany
| | - Yves Joly
- CNRS, Grenoble INPInstitut NéelUniversité Grenoble Alpes38042GrenobleFrance
| | - Stepan N. Kalmykov
- Department of ChemistryLomonosov Moscow State University119991MoscowRussia
| | - Kristina O. Kvashnina
- The Rossendorf Beamline at ESRFThe European SynchrotronCS4022038043Grenoble Cedex 9France
- Institute of Resource EcologyHelmholtz Zentrum Dresden-Rossendorf (HZDR), PO Box 51011901314DresdenGermany
- Department of ChemistryLomonosov Moscow State University119991MoscowRussia
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19
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Gerber E, Romanchuk AY, Weiss S, Bauters S, Schacherl B, Vitova T, Hübner R, Shams Aldin Azzam S, Detollenaere D, Banerjee D, Butorin SM, Kalmykov SN, Kvashnina KO. Insight into the structure–property relationship of UO 2 nanoparticles. Inorg Chem Front 2021. [DOI: 10.1039/d0qi01140a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We show that the structural and electronic properties of UO2 NPs (2–3 nm) are similar to those of bulk UO2 under inert conditions, with U(iv) as the dominating oxidation state, though NPs oxidize with time and under the X-ray beam.
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20
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Romanchuk AY, Vlasova IE, Kalmykov SN. Speciation of Uranium and Plutonium From Nuclear Legacy Sites to the Environment: A Mini Review. Front Chem 2020; 8:630. [PMID: 32903456 PMCID: PMC7434977 DOI: 10.3389/fchem.2020.00630] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 06/17/2020] [Indexed: 12/02/2022] Open
Abstract
The row of 15 chemical elements from Ac to Lr with atomic numbers from 89 to 103 are known as the actinides, which are all radioactive. Among them, uranium and plutonium are the most important as they are used in the nuclear fuel cycle and nuclear weapon production. Since the beginning of national nuclear programs and nuclear tests, many radioactively contaminated nuclear legacy sites, have been formed. This mini review covers the latest experimental, modeling, and case studies of plutonium and uranium migration in the environment, including the speciation of these elements and the chemical reactions that control their migration pathways.
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Affiliation(s)
| | | | - Stepan N. Kalmykov
- Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia
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