1
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Srivastava DJ, Grandinetti PJ. Statistical learning of NMR tensors from 2D isotropic/anisotropic correlation nuclear magnetic resonance spectra. J Chem Phys 2020; 153:134201. [PMID: 33032428 DOI: 10.1063/5.0023345] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Many linear inversion problems involving Fredholm integrals of the first kind are frequently encountered in the field of magnetic resonance. One important application is the direct inversion of a solid-state nuclear magnetic resonance (NMR) spectrum containing multiple overlapping anisotropic subspectra to obtain a distribution of the tensor parameters. Because of the ill-conditioned nature of this inverse problem, we investigate the use of the truncated singular value decomposition and the smooth least absolute shrinkage and selection operator based regularization methods, which (a) stabilize the solution and (b) promote sparsity and smoothness in the solution. We also propose an unambiguous representation for the anisotropy parameters using a piecewise polar coordinate system to minimize rank deficiency in the inversion kernel. To obtain the optimum tensor parameter distribution, we implement the k-fold cross-validation, a statistical learning method, to determine the hyperparameters of the regularized inverse problem. In this article, we provide the details of the linear-inversion method along with numerous illustrative applications on purely anisotropic NMR spectra, both synthetic and experimental two-dimensional spectra correlating the isotropic and anisotropic frequencies.
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Affiliation(s)
- Deepansh J Srivastava
- Department of Chemistry, Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA
| | - Philip J Grandinetti
- Department of Chemistry, Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA
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2
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Prasad S, Gaddam A, Jana A, Kant S, Sinha PK, Tripathy S, Annapurna K, Ferreira JMF, Allu AR, Biswas K. Structure and Stability of High CaO- and P 2O 5-Containing Silicate and Borosilicate Bioactive Glasses. J Phys Chem B 2019; 123:7558-7569. [PMID: 31403295 DOI: 10.1021/acs.jpcb.9b02455] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The present work elucidates about the structure of bioactive glasses having chemical compositions expressed as (mol %) (50.0 - x)SiO2-xB2O3-9.3Na2O-37CaO-3.7P2O5, where x = 0.0, 12.5, 25, and 37.5, and establishes a correlation between the structure and thermal stability. The structural modifications in the parent boron-free glass (B0) with the gradual substitutions of B2O3 for SiO2 are assessed by Raman and 29Si, 31P, 11B, and 23Na magic angle spinning (MAS)-nuclear magnetic resonance (NMR) spectroscopies. The structural studies reveal the presence of QSi2 and QSi3 structural units in both silicate and borosilicate glasses. However, QSi4(3B) units additionally form upon incorporating B2O3 in B0 glass. B-containing silicate glasses exhibit both three-coordinated boron (BIII) and four-coordinated boron (BIV) units. The 31P MAS-NMR studies reveal that the majority of phosphate species exist as isolated orthophosphate (QP0) units. The incorporation of B2O3 in B0 glass increases the cross-linking between the SiO4 and BO4 structural units. However, incorporation of B2O3 lowers the glass thermal stability (ΔT), as shown by differential scanning calorimetry. Although both silicate and borosilicate glasses exhibit good in vitro apatite-forming ability and cell compatibility, the bactericidal action against Escherichia coli bacteria is more evident in borosilicate glass in comparison to silicate base glass. The controlled release of (BO3)3- ions from boron-modified bioactive glasses improves both the cell proliferation and the antibacterial properties, making them promising for hard tissue engineering applications.
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Affiliation(s)
| | - Anuraag Gaddam
- Department of Materials and Ceramic Engineering, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
| | | | | | | | | | | | - José M F Ferreira
- Department of Materials and Ceramic Engineering, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
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3
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Moran RF, Dawson DM, Ashbrook SE. Exploiting NMR spectroscopy for the study of disorder in solids. INT REV PHYS CHEM 2017. [DOI: 10.1080/0144235x.2017.1256604] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Robert F. Moran
- School of Chemistry, EaStCHEM and St Andrews Centre of Magnetic Resonance, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
| | - Daniel M. Dawson
- School of Chemistry, EaStCHEM and St Andrews Centre of Magnetic Resonance, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
| | - Sharon E. Ashbrook
- School of Chemistry, EaStCHEM and St Andrews Centre of Magnetic Resonance, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
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4
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Gambuzzi E, Pedone A, Menziani MC, Angeli F, Florian P, Charpentier T. Calcium environment in silicate and aluminosilicate glasses probed by ⁴³Ca MQMAS NMR experiments and MD-GIPAW calculations. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2015; 68-69:31-36. [PMID: 25912209 DOI: 10.1016/j.ssnmr.2015.04.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Revised: 03/31/2015] [Accepted: 04/02/2015] [Indexed: 06/04/2023]
Abstract
⁴³Ca MQMAS NMR spectra of three silica-based glasses in which Ca²⁺ ions play different structural roles have been collected and processed in order to extract the underlying NMR parameter distributions. The NMR parameters have been interpreted with the help of molecular dynamics simulations and DFT-GIPAW calculations. This synergetic experimental-computational approach has allowed us to investigate the Ca environment, to estimate Ca coordination numbers from MD-derived models, and to push further the discussion about ⁴³Ca NMR sensitivity to the first and second coordination spheres: ⁴³Ca δiso and Ca-O distance can be successfully correlated as a function of Ca coordination number.
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Affiliation(s)
- Elisa Gambuzzi
- Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Modena e Reggio Emilia, Via G. Campi 183, 41125 Modena, Italy
| | - Alfonso Pedone
- Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Modena e Reggio Emilia, Via G. Campi 183, 41125 Modena, Italy
| | - Maria Cristina Menziani
- Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Modena e Reggio Emilia, Via G. Campi 183, 41125 Modena, Italy
| | - Frédéric Angeli
- CEA Marcoule, DEN, Laboratoire d׳étude du Comportement à Long Terme, 30207 Bagnols-sur-Cèze, France
| | - Pierre Florian
- CEMHTI-CNRS UPR3079, Conditions Extrêmes et Matériaux: Haute Température et Irradiation, Av. de la Recherche Scientifique, 45071 Orléans cedex 2, France
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5
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Gambuzzi E, Charpentier T, Menziani MC, Pedone A. Computational interpretation of 23Na MQMAS NMR spectra: A comprehensive investigation of the Na environment in silicate glasses. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2014.08.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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6
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Svenson MN, Thirion LM, Youngman RE, Mauro JC, Rzoska SJ, Bockowski M, Smedskjaer MM. Pressure-induced changes in interdiffusivity and compressive stress in chemically strengthened glass. ACS APPLIED MATERIALS & INTERFACES 2014; 6:10436-10444. [PMID: 24911917 DOI: 10.1021/am5019868] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Glass exhibits a significant change in properties when subjected to high pressure because the short- and intermediate-range atomic structures of glass are tunable through compression. Understanding the link between the atomic structure and macroscopic properties of glass under high pressure is an important scientific problem because the glass structures obtained via quenching from elevated pressure may give rise to properties unattainable under standard ambient pressure conditions. In particular, the chemical strengthening of glass through K(+)-for-Na(+) ion exchange is currently receiving significant interest due to the increasing demand for stronger and more damage-resistant glass. However, the interplay among isostatic compression, pressure-induced changes in alkali diffusivity, compressive stress generated through ion exchange, and the resulting mechanical properties are poorly understood. In this work, we employ a specially designed gas pressure chamber to compress bulk glass samples isostatically up to 1 GPa at elevated temperature before or after the ion exchange treatment of a commercial sodium-magnesium aluminosilicate glass. Compression of the samples prior to ion exchange leads to a decreased Na(+)-K(+) interdiffusivity, increased compressive stress, and slightly increased hardness. Compression after the ion exchange treatment changes the shape of the potassium-sodium diffusion profiles and significantly increases glass hardness. We discuss these results in terms of the underlying structural changes in network-modifier environments and overall network densification.
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7
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Smith AL, Raison PE, Martel L, Charpentier T, Farnan I, Prieur D, Hennig C, Scheinost AC, Konings RJM, Cheetham AK. A 23Na Magic Angle Spinning Nuclear Magnetic Resonance, XANES, and High-Temperature X-ray Diffraction Study of NaUO3, Na4UO5, and Na2U2O7. Inorg Chem 2013; 53:375-82. [DOI: 10.1021/ic402306c] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- A. L. Smith
- European Commission,
Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe, Germany
- Department of Materials Science
and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom
| | - P. E. Raison
- European Commission,
Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe, Germany
| | - L. Martel
- European Commission,
Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe, Germany
| | - T. Charpentier
- CEA, IRAMIS, SIS2M, Laboratoire de Structure et Dynamique
par Résonance Magnétique, UMR CEA/CNRS 3299, 91191 Gif-sur-Yvette, France
| | - I. Farnan
- Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, United Kingdom, and
| | - D. Prieur
- European Commission,
Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe, Germany
| | - C. Hennig
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf (HZDR), , P.O. Box 10119, 01314 Dresden, Germany
| | - A. C. Scheinost
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf (HZDR), , P.O. Box 10119, 01314 Dresden, Germany
| | - R. J. M. Konings
- European Commission,
Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe, Germany
| | - A. K. Cheetham
- Department of Materials Science
and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom
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8
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Lee SK. Effect of pressure on structure of oxide glasses at high pressure: Insights from solid-state NMR of quadrupolar nuclides. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2010; 38:45-57. [PMID: 21074379 DOI: 10.1016/j.ssnmr.2010.10.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Revised: 10/15/2010] [Accepted: 10/18/2010] [Indexed: 05/30/2023]
Abstract
Revealing the structure of oxide glasses at high pressure remains a fundamental yet difficult problem in modern physical and chemical sciences. The recent advances in solid-state NMR techniques used for quadrupolar nuclides offer a considerably improved resolution of atomic sites, unveiling previously unknown structural details of oxides glasses at high pressure. Here, we present an overview of the recent progress and insights by high-resolution multi-nuclear triple quantum magic angle spinning (3QMAS) NMR into pressure-induced changes in coordination number, connectivity, and topological disorder in oxide glasses quenched from melts at high pressure. (11)B and (27)Al 3QMAS NMR studies of oxide glasses show that the formation of highly coordinated Al (([5,6])Al) and four coordinated ([4])B are prevalent at high pressure up to 8 GPa. The formation of oxygen clusters linking these highly coordinated framework units and Si (e.g., ([5,6])Al-O-([4])Si, ([5,6])Si-O-([4])Si, and Na-O-([5,6])Si) is observed in the (17)O NMR spectra at higher pressure, leading to an overall increase in the degree of polymerization with pressure. (23)Na MAS NMR spectra of diverse oxide glasses at high pressure and high magnetic field also indicate that the Na-O bond distance may decrease with pressure. Pressure-induced changes in structurally relevant NMR parameters such as the (17)O quadrupolar coupling product (P(q)) for the Si-O-Si cluster and (27)Al P(q) for Al sites in oxide glasses indicate the occurrence of pressure-induced reductions in the Si-O-Si angle and an increase in the Al-O bond length distribution with pressure, indicating an increase in the overall topological disorder in oxide glasses with pressure. All the pressure-induced changes in structure and topology are characterized by strong composition dependence. These experimental results highlight a new opportunity to investigate the molecular structures of silicate melts at high pressure and reveal connections between the microscopic signatures of anomalous and non-linear changes in the macroscopic properties of the corresponding liquids. While many challenges still remain in the synthesis of oxide glasses with wider range of melt composition at higher pressure above 12 GPa, recent progress in enhancement of sensitivity and resolution in the solid state NMR hold strong promise for study exploring additional details of connectivity among quadrupolar nuclides and medium-range order of the more complex, multi-components glasses at high pressure.
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Affiliation(s)
- Sung Keun Lee
- Laboratory of Physics and Chemistry of Earth Materials, School of Earth and Environmental Sciences, Seoul National University, Seoul 151-742, Republic of Korea.
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9
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Hanna J, Pike K, Charpentier T, Kemp T, Smith M, Lucier B, Schurko R, Cahill L. A93Nb Solid-State NMR and Density Functional Theory Study of Four- and Six-Coordinate Niobate Systems. Chemistry 2010; 16:3222-39. [DOI: 10.1002/chem.200901581] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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10
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Abo-Mosallam HA, Hill RG, Karpukhina N, Law RV. MAS-NMR studies of glasses and glass-ceramics based on a clinopyroxene–fluorapatite system. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/b915573b] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Griffith CS, Luca V, Hanna JV, Pike KJ, Smith ME, Thorogood GS. Microcrystalline Hexagonal Tungsten Bronze. 1. Basis of Ion Exchange Selectivity for Cesium and Strontium. Inorg Chem 2009; 48:5648-62. [DOI: 10.1021/ic801294x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christopher S. Griffith
- Australian Nuclear Science and Technology Organisation, ANSTO Minerals, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Vittorio Luca
- Australian Nuclear Science and Technology Organisation, ANSTO Minerals, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - John V. Hanna
- Australian Nuclear Science and Technology Organisation, ANSTO Minerals, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Kevin J. Pike
- Department of Physics, University of Warwick, Gibbet Hill Rd., Coventry CV4 7AL, United Kingdom
| | - Mark E. Smith
- Department of Physics, University of Warwick, Gibbet Hill Rd., Coventry CV4 7AL, United Kingdom
| | - Gordon S. Thorogood
- Australian Nuclear Science and Technology Organisation, ANSTO Minerals, New Illawarra Road, Lucas Heights, NSW 2234, Australia
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12
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Luca V, Griffith CS, Hanna JV. Microcrystalline Hexagonal Tungsten Bronze. 2. Dehydration Dynamics. Inorg Chem 2009; 48:5663-76. [DOI: 10.1021/ic801295c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Vittorio Luca
- Australian Nuclear Science and Technology Organisation, ANSTO Minerals, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Christopher S. Griffith
- Australian Nuclear Science and Technology Organisation, ANSTO Minerals, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - John V. Hanna
- Australian Nuclear Science and Technology Organisation, ANSTO Minerals, New Illawarra Road, Lucas Heights, NSW 2234, Australia
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13
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Angeli F, Gaillard M, Jollivet P, Charpentier T. Contribution of 43Ca MAS NMR for probing the structural configuration of calcium in glass. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.04.036] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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14
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Body M, Legein C, Buzaré JY, Silly G. The Relationship Between27Al Quadrupolar Parameters and AlF63– Octahedron Connectivity in Crystalline and Glassy Fluoroaluminates. Eur J Inorg Chem 2007. [DOI: 10.1002/ejic.200601148] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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15
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Lee SK, Lee BH. Atomistic Origin of Germanate Anomaly in GeO2 and Na-Germanate Glasses: Insights from Two-Dimensional 17O NMR and Quantum Chemical Calculations. J Phys Chem B 2006; 110:16408-12. [PMID: 16913771 DOI: 10.1021/jp063847b] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The prominent problem in archetypal germanate glasses is the germanate anomaly where the density exhibits maxima at 15-20 mol % of the alkali oxide content. Here we report (17)O two-dimensional NMR spectra for GeO(2) and Na-germanate glasses where the presence of both bridging oxygen linking ([4])Ge and highly coordinated Ge (([5,6])Ge-O-([4])Ge) and nonbridging oxygen, and an increase in topological disorder are demonstrated at the density maximum, manifesting atomic origins of the anomaly. These densification mechanisms in germanate glasses with Na content are remarkably similar to densification in v-B(2)O(3) with pressure.
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Affiliation(s)
- Sung Keun Lee
- Laboratory of Physics and Chemistry of Earth Materials, School of Earth and Environmental Sciences, Seoul National University, Seoul 151-742, Korea.
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16
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Aubin-Chevaldonnet V, Gourier D, Caurant D, Esnouf S, Charpentier T, Costantini JM. Paramagnetic defects induced by electron irradiation in barium hollandite ceramics for caesium storage. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2006; 18:4007-4027. [PMID: 21690754 DOI: 10.1088/0953-8984/18/16/009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We have studied by electron paramagnetic resonance the mechanism of defect production by electron irradiation in barium hollandite, a material used for immobilization of radioactive caesium. The irradiation conditions were the closest possible to those occurring in Cs storage waste forms. Three paramagnetic defects were observed, independently of the irradiation conditions. A hole centre (H centre) is attributed to a superoxide ion O(2)(-) originating from hole trapping by interstitial oxygen produced by electron irradiation. An electron centre (E(1) centre) is attributed to a Ti(3+) ion adjacent to the resulting oxygen vacancy. Another electron centre (E(2) centre) is attributed to a Ti(3+) ion in a cation site adjacent to an extra Ba(2+) ion in a neighbouring tunnel, originating from barium displacement by elastic collisions. Comparison of the effects of external irradiations by electrons with the β-decay of Cs in storage waste forms is discussed. It is concluded that the latter would be dominated by E(1) and H centres rather than E(2) centres.
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Affiliation(s)
- V Aubin-Chevaldonnet
- CNRS, Ecole Nationale Supérieure de Chimie de Paris (ENSCP, ParisTech), Laboratoire de Chimie de la Matière Condensée de Paris, UMR-CNRS 7574, 11, rue P et M Curie, 75231 Paris Cedex 05, France
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17
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Wendlandt M, van Beek JD, Suter UW, Meier BH. Determination of Orientational Order in Deformed Glassy PMMA from Solid-State NMR Data. Macromolecules 2005. [DOI: 10.1021/ma0512105] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michael Wendlandt
- Department of Materials, ETH Zurich, 8093 Zürich, Switzerland, and Physical Chemistry, ETH Zurich, 8093 Zürich, Switzerland
| | - Jacco D. van Beek
- Department of Materials, ETH Zurich, 8093 Zürich, Switzerland, and Physical Chemistry, ETH Zurich, 8093 Zürich, Switzerland
| | - Ulrich W. Suter
- Department of Materials, ETH Zurich, 8093 Zürich, Switzerland, and Physical Chemistry, ETH Zurich, 8093 Zürich, Switzerland
| | - Beat H. Meier
- Department of Materials, ETH Zurich, 8093 Zürich, Switzerland, and Physical Chemistry, ETH Zurich, 8093 Zürich, Switzerland
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18
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Sakellariou D, Jacquinot JF, Charpentier T. 2D correlation spectra of isotropic and anisotropic 29Si chemical shifts in crystalline and amorphous natural abundance materials under very slow sample rotation. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.06.046] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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19
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Yang H, Walton RI, Antonijevic S, Wimperis S, Hannon AC. Local Order of Amorphous Zeolite Precursors from 29Si{H} CPMAS and 27Al and 23Na MQMAS NMR and Evidence for the Nature of Medium-Range Order from Neutron Diffraction. J Phys Chem B 2004. [DOI: 10.1021/jp037887g] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Huaixin Yang
- Department of Chemistry, University of Exeter, Stocker Road, Exeter EX4 4QD, U.K
| | - Richard I. Walton
- Department of Chemistry, University of Exeter, Stocker Road, Exeter EX4 4QD, U.K
| | - Sasa Antonijevic
- Department of Chemistry, University of Exeter, Stocker Road, Exeter EX4 4QD, U.K
| | - Stephen Wimperis
- Department of Chemistry, University of Exeter, Stocker Road, Exeter EX4 4QD, U.K
| | - Alex C. Hannon
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, U.K
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20
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van Beek JD, Meier BH, Schäfer H. Inverse methods in two-dimensional NMR spectral analysis. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2003; 162:141-157. [PMID: 12762991 DOI: 10.1016/s1090-7807(02)00193-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Solid-state NMR is a valuable technique for the study of disordered materials. Analysis of such spectra usually involves solution of so-called ill-posed inverse problems. Here we present a strategy for the analysis of two-parameter two-dimensional NMR problems and test it on 2D DECODER and DOQSY experiments. Using Monte Carlo tests, constraints are determined for the resolution and accuracy of the analysis for both experiments. The methods are finally applied to spectra of spider dragline silk, a heterogeneous solid fibrous protein.
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Affiliation(s)
- Jacco D van Beek
- ETH Zurich, Physical Chemistry, ETH-Hönggerberg, CH-8093, Zurich, Switzerland
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21
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Ai X, Deng F, Dong J, Chen L, Ye C. Stability of Layered Sodium Disilicate during Hydration Process As Studied by Multinuclear Solid State NMR Spectroscopy. J Phys Chem B 2002. [DOI: 10.1021/jp020458i] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xuanjun Ai
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, The Chinese Academy of Sciences, Wuhan 430071, P. R. China, and Research Institute of Special Chemicals, Taiyuan University of Technology, Taiyuan 030024, P. R. China
| | - Feng Deng
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, The Chinese Academy of Sciences, Wuhan 430071, P. R. China, and Research Institute of Special Chemicals, Taiyuan University of Technology, Taiyuan 030024, P. R. China
| | - Jinxiang Dong
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, The Chinese Academy of Sciences, Wuhan 430071, P. R. China, and Research Institute of Special Chemicals, Taiyuan University of Technology, Taiyuan 030024, P. R. China
| | - Lei Chen
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, The Chinese Academy of Sciences, Wuhan 430071, P. R. China, and Research Institute of Special Chemicals, Taiyuan University of Technology, Taiyuan 030024, P. R. China
| | - Chaohui Ye
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, The Chinese Academy of Sciences, Wuhan 430071, P. R. China, and Research Institute of Special Chemicals, Taiyuan University of Technology, Taiyuan 030024, P. R. China
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Millot Y, Man PP. Procedures for labeling the high-resolution axis of two-dimensional MQ-MAS NMR spectra of half-integer quadrupole spins. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2002; 21:21-43. [PMID: 11949815 DOI: 10.1006/snmr.2001.0043] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The increasing development and application of the multiple-quantum MAS NMR for half-integer quadrupole spins has led to various RF pulse sequences for improving the excitation of multiple-quantum coherences and their conversion to single-quantum coherences. As a result, several conventions for labeling the Fl dimension of a 2D MQ-MAS spectrum appear in the literature. The corresponding relations for extracting the isotropic chemical shift, the quadrupole coupling constant, and the asymmetry parameter from experimental data are not always provided. We analyze these various conventions systematically and propose a new one, similar to that introduced by J.-P. Amoureux and C. Fernandez (2000, Solid State NMR 10, 339-343). These various conventions are illustrated with 27Al (I = 5/2) nuclei in aluminum acetylacetonate Al(CH3COCHCOCH3)3. Another experimental problem often met, the aliasing of peaks in the 2D spectrum, is analyzed and illustrated with 27Al (I = 5/2) in NH4Y zeolite and 23Na (I = 3/2) in sodium pyrophosphate Na4P2O7.
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Affiliation(s)
- Yannick Millot
- Systèmes Interfaciaux a l'Echelle Nanométrique, CNRS FRE 2312, Laboratoire de Chimie des Surfaces, Université Pierre et Marie Curie, Paris, France
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Prasad S, Zhao P, Huang J, Fitzgerald JJ, Shore JS. Niobium-93 MQMAS NMR spectroscopic study of alkali and lead niobates. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2001; 19:45-62. [PMID: 11407602 DOI: 10.1006/snmr.2000.0022] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
93Nb (I = 9/2) multiple-quantum magic-angle spinning (MQMAS) NMR spectra of a series of inorganic niobates have been measured. 93Nb MQMAS spectroscopy yields spectra with typically an order of magnitude higher resolution than that obtainable with 93Nb MAS spectroscopy and 93Nb dynamic-angle spinning (DAS) spectroscopy. For example, the full-width at half-maximums of the 93Nb resonances of LiNbO3 were 9 (MAS), 5.8 (DAS), and 0.7 kHz (MQMAS). Broadening of the 93Nb MAS and DAS spectra is due to the second-order quadrupolar and homonuclear dipolar interactions, respectively. The quadrupolar products (P(O)) and isotropic chemical shifts (delta(iso)) of the 93Nb resonances of LiNbO3, NaNbO3, PbNb2O6, Pb2Nb2O7, Pb3Nb2O8, Pb3Nb4O15, Pb3Nb4O13, and Pb1.83Nb1.71Mg0.29O6.39 were determined from MQMAS spectra and range from 13.6 to 26.8 MHz and from -951 to -1113 ppm, respectively. Resonances with relatively large quadrupolar coupling constants (> 30 MHz) were not observed using MQMAS spectroscopy, but were detected using nutation spectroscopy. The applicability and limitations of MQMAS spectroscopy in studying inorganic niobates containing multiple 93Nb resonances are addressed and compared with those of MAS, nutation, and DAS spectroscopies.
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Affiliation(s)
- S Prasad
- Department of Chemistry and Biochemistry, South Dakota State University, Brookings 57007, USA
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