1
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Koppe J, Frerichs JE, Hansen MR. Pushing the Detection Limit of Static Wideline NMR Spectroscopy Using Ultrafast Frequency-Swept Pulses. J Phys Chem Lett 2023; 14:10748-10753. [PMID: 38010530 DOI: 10.1021/acs.jpclett.3c02758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
We report a simple design strategy for wideband uniform-rate smooth truncation (WURST) pulses that enables ultrafast frequency sweeps to maximize the sensitivity of Carr-Purcell-Meiboom-Gill (CPMG) acquisition in static wideline nuclear magnetic resonance (NMR). Three compelling examples showcase the advantage of ultrafast frequency sweeps over currently employed WURST-CPMG protocols, demonstrating the potential of investigating materials that are typically inaccessible to static wideline NMR techniques, e.g., paramagnetic solids with short homogeneous transverse relaxation times.
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Affiliation(s)
- Jonas Koppe
- Institute for Physical Chemistry, University of Münster, Corrensstrasse 28/30, DE-48149 Münster, Germany
- Centre de RMN Très Hauts Champs de Lyon (UMR5082 - CNRS, ENS Lyon, UCB Lyon 1), Université de Lyon, 5 rue de la Doua, 69100 Villeurbanne, France
| | - Joop Enno Frerichs
- Institute for Physical Chemistry, University of Münster, Corrensstrasse 28/30, DE-48149 Münster, Germany
| | - Michael Ryan Hansen
- Institute for Physical Chemistry, University of Münster, Corrensstrasse 28/30, DE-48149 Münster, Germany
- Center for Multiscale Theory and Computation (CMTC), University of Münster, Corrensstrasse 40, DE-48149 Münster, Germany
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2
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Slebodnick C. X-ray Lite: A 1-credit pass/fail crystallography course. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2021; 8:020404. [PMID: 33758766 PMCID: PMC7955856 DOI: 10.1063/4.0000091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 02/23/2021] [Indexed: 06/12/2023]
Affiliation(s)
- Carla Slebodnick
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, USA
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3
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Czernek J, Kobera L, Havlák L, Czerneková V, Rohlíček J, Bárta J, Brus J. Probing the 91Zr NMR parameters in the solid state by a combination of DFT calculations and experiments. Chem Phys Lett 2020. [DOI: 10.1016/j.cplett.2019.136855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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4
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Grekov D, Vancompernolle T, Taoufik M, Delevoye L, Gauvin RM. Solid-state NMR of quadrupolar nuclei for investigations into supported organometallic catalysts: scope and frontiers. Chem Soc Rev 2018; 47:2572-2590. [DOI: 10.1039/c7cs00682a] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The scope, limitations and outlooks of half-integer quadrupolar nuclei NMR as applied to supported catalysts characterization are discussed.
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Affiliation(s)
- D. Grekov
- Univ. Lille
- CNRS
- Centrale Lille
- ENSCL
- Univ. Artois
| | | | - M. Taoufik
- Laboratoire de Chimie
- Catalyse
- Polyméres et Procédés
- UMR 5265 CNRS/ESCPE-Lyon/UCBL
- ESCPE Lyon
| | - L. Delevoye
- Univ. Lille
- CNRS
- Centrale Lille
- ENSCL
- Univ. Artois
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5
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Copéret C, Liao WC, Gordon CP, Ong TC. Active Sites in Supported Single-Site Catalysts: An NMR Perspective. J Am Chem Soc 2017; 139:10588-10596. [DOI: 10.1021/jacs.6b12981] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Christophe Copéret
- Department of Chemistry and
Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5, CH-8093 Zürich, Switzerland
| | - Wei-Chih Liao
- Department of Chemistry and
Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5, CH-8093 Zürich, Switzerland
| | - Christopher P. Gordon
- Department of Chemistry and
Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5, CH-8093 Zürich, Switzerland
| | - Ta-Chung Ong
- Department of Chemistry and
Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5, CH-8093 Zürich, Switzerland
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6
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Jaroszewicz MJ, Frydman L, Schurko RW. Relaxation-Assisted Separation of Overlapping Patterns in Ultra-Wideline NMR Spectra. J Phys Chem A 2016; 121:51-65. [DOI: 10.1021/acs.jpca.6b10007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michael J. Jaroszewicz
- Department
of Chemistry and Biochemistry, University of Windsor, Windsor, ON, Canada N9B 3P4
| | - Lucio Frydman
- Department
of Chemical Physics, Weizmann Institute of Science, Rehovot, 76100 Israel
| | - Robert W. Schurko
- Department
of Chemistry and Biochemistry, University of Windsor, Windsor, ON, Canada N9B 3P4
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7
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Kobayashi T, Perras FA, Goh TW, Metz TL, Huang W, Pruski M. DNP-Enhanced Ultrawideline Solid-State NMR Spectroscopy: Studies of Platinum in Metal-Organic Frameworks. J Phys Chem Lett 2016; 7:2322-2327. [PMID: 27266444 DOI: 10.1021/acs.jpclett.6b00860] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Ultrawideline dynamic nuclear polarization (DNP)-enhanced (195)Pt solid-state NMR (SSNMR) spectroscopy and theoretical calculations are used to determine the coordination of atomic Pt species supported within the pores of metal-organic frameworks (MOFs). The (195)Pt SSNMR spectra, with breadths reaching 10 000 ppm, were obtained by combining DNP with broadbanded cross-polarization and CPMG acquisition. Although the DNP enhancements in static samples are lower than those typically observed under magic-angle spinning conditions, the presented measurements would be very challenging using the conventional SSNMR methods. The DNP-enhanced ultrawideline NMR spectra served to separate signals from cis- and trans-coordinated atomic Pt(2+) species supported on the UiO-66-NH2 MOF. Additionally, the data revealed a dominance of kinetic effects in the formation of Pt(2+) complexes and the thermodynamic effects in their reduction to nanoparticles. A single cis-coordinated Pt(2+) complex was confirmed in MOF-253.
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Affiliation(s)
- Takeshi Kobayashi
- Ames Laboratory, U.S. Department of Energy , Ames, Iowa 50011, United States
| | - Frédéric A Perras
- Ames Laboratory, U.S. Department of Energy , Ames, Iowa 50011, United States
| | - Tian Wei Goh
- Department of Chemistry, Iowa State University , Ames, Iowa 50011, United States
| | - Tanner L Metz
- Department of Chemistry, Iowa State University , Ames, Iowa 50011, United States
| | - Wenyu Huang
- Ames Laboratory, U.S. Department of Energy , Ames, Iowa 50011, United States
- Department of Chemistry, Iowa State University , Ames, Iowa 50011, United States
| | - Marek Pruski
- Ames Laboratory, U.S. Department of Energy , Ames, Iowa 50011, United States
- Department of Chemistry, Iowa State University , Ames, Iowa 50011, United States
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8
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Conley MP, Lapadula G, Sanders K, Gajan D, Lesage A, del Rosal I, Maron L, Lukens WW, Copéret C, Andersen RA. The Nature of Secondary Interactions at Electrophilic Metal Sites of Molecular and Silica-Supported Organolutetium Complexes from Solid-State NMR Spectroscopy. J Am Chem Soc 2016; 138:3831-43. [PMID: 26887899 DOI: 10.1021/jacs.6b00071] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Lu[CH(SiMe3)2]3 reacts with [SiO2-700] to give [(≡SiO)Lu[CH(SiMe3)2]2] and CH2(SiMe3)2. [(≡SiO)Lu[CH(SiMe3)2]2] is characterized by solid-state NMR and EXAFS spectroscopy, which show that secondary Lu···C and Lu···O interactions, involving a γ-CH3 and a siloxane bridge, are present. From X-ray crystallographic analysis, the molecular analogues Lu[CH(SiMe3)2]3-x[O-2,6-tBu-C6H3]x (x = 0-2) also have secondary Lu···C interactions. The (1)H NMR spectrum of Lu[CH(SiMe3)2]3 shows that the -SiMe3 groups are equivalent to -125 °C and inequivalent below that temperature, ΔG(⧧)(Tc = 148 K) = 7.1 kcal mol(-1). Both -SiMe3 groups in Lu[CH(SiMe3)2]3 have (1)JCH = 117 ± 1 Hz at -140 °C. The solid-state (13)C CPMAS NMR spectrum at 20 °C shows three chemically inequivalent resonances in the area ratio of 4:1:1 (12:3:3); the J-resolved spectra for each resonance give (1)JCH = 117 ± 2 Hz. The (29)Si CPMAS NMR spectrum shows two chemically inequivalent resonances with different values of chemical shift anisotropy. Similar observations are obtained for Lu[CH(SiMe3)2]3-x[O-2,6-tBu-C6H3]x (x = 1 and 2). The spectroscopic data point to short Lu···Cγ contacts corresponding to 3c-2e Lu···Cγ-Siβ interactions, which are supported by DFT calculations. Calculated natural bond orbital (NBO) charges show that Cγ carries a negative charge, while Lu, Hγ, and Siβ carry positive charges; as the number of O-based ligands increases so does the positive charge at Lu, which in turns shortens the Lu···Cγ distance. The change in NBO charges and the resulting changes in the spectroscopic and crystallographic properties show how ligands and surface-support sites rearrange to accommodate these changes, consistent with Pauling's electroneutrality concept.
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Affiliation(s)
- Matthew P Conley
- Department of Chemistry and Applied Biosciences, ETH Zürich , Vladimir Prelog Weg 1-5, CH-8093 Zürich, Switzerland
| | - Giuseppe Lapadula
- Department of Chemistry and Applied Biosciences, ETH Zürich , Vladimir Prelog Weg 1-5, CH-8093 Zürich, Switzerland
| | - Kevin Sanders
- Centre de RMN à Très Hauts Champs, CRNS/ENS-Lyon/UCB Lyon 1, Université de Lyon , 5 rue de la Doua, 69100 Villeurbanne, France
| | - David Gajan
- Centre de RMN à Très Hauts Champs, CRNS/ENS-Lyon/UCB Lyon 1, Université de Lyon , 5 rue de la Doua, 69100 Villeurbanne, France
| | - Anne Lesage
- Centre de RMN à Très Hauts Champs, CRNS/ENS-Lyon/UCB Lyon 1, Université de Lyon , 5 rue de la Doua, 69100 Villeurbanne, France
| | - Iker del Rosal
- Université de Toulouse and CNRS, LPCNO INSA/UPS/CNRS , 135 avenue de Rangueil, 31077 Toulouse Cedex 4, France
| | - Laurent Maron
- Université de Toulouse and CNRS, LPCNO INSA/UPS/CNRS , 135 avenue de Rangueil, 31077 Toulouse Cedex 4, France
| | - Wayne W Lukens
- Chemical Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich , Vladimir Prelog Weg 1-5, CH-8093 Zürich, Switzerland
| | - Richard A Andersen
- Department of Chemistry, University of California , Berkeley, California 94720, United States
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9
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Grekov D, Bouhoute Y, Del Rosal I, Maron L, Taoufik M, Gauvin RM, Delevoye L. 17O MAS NMR studies of oxo-based olefin metathesis catalysts: a critical assessment of signal enhancement methods. Phys Chem Chem Phys 2016; 18:28157-28163. [DOI: 10.1039/c6cp04667c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We assessed the DFS parameters for robust and optimal signal enhancement in 17O NMR studies of silica-supported catalysts.
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Affiliation(s)
- D. Grekov
- Unité de Catalyse et de Chimie du Solide
- CNRS UMR 8181
- Université de Lille
- F-59655 Villeneuve d’Ascq
- France
| | - Y. Bouhoute
- Laboratoire de Chimie
- Catalyse, Polymères et Procédés
- UMR 5265 CNRS
- UCBL
- ESCPE Lyon
| | - I. Del Rosal
- Laboratoire de Physico-Chimie des Nano-Objets
- CNRS UMR 5215
- Université de Toulouse
- INSA
- UPS
| | - L. Maron
- Laboratoire de Physico-Chimie des Nano-Objets
- CNRS UMR 5215
- Université de Toulouse
- INSA
- UPS
| | - M. Taoufik
- Laboratoire de Chimie
- Catalyse, Polymères et Procédés
- UMR 5265 CNRS
- UCBL
- ESCPE Lyon
| | - R. M. Gauvin
- Unité de Catalyse et de Chimie du Solide
- CNRS UMR 8181
- Université de Lille
- F-59655 Villeneuve d’Ascq
- France
| | - L. Delevoye
- Unité de Catalyse et de Chimie du Solide
- CNRS UMR 8181
- Université de Lille
- F-59655 Villeneuve d’Ascq
- France
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10
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Tijssen KCH, Blaakmeer ESM, Kentgens APM. Solid-state NMR studies of Ziegler-Natta and metallocene catalysts. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2015; 68-69:37-56. [PMID: 25957882 DOI: 10.1016/j.ssnmr.2015.04.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 03/30/2015] [Accepted: 04/02/2015] [Indexed: 06/04/2023]
Abstract
Ziegler-Natta catalysts are the workhorses of polyolefin production. However, although they have been used and intensively studied for half a century, there is still no comprehensive picture of their mechanistic operation. New techniques are needed to gain more insight in these catalysts. Solid-state NMR has reached a high level of sophistication over the last few decades and holds great promise for providing a deeper insight in Ziegler-Natta catalysis. This review outlines the possibilities for solid-state NMR to characterize the different components and interactions in Ziegler-Natta and metallocene catalysts. An overview is given of some of the expected mechanisms and the resulting polymer microstructure and other characteristics. In the second part of this review we present studies that have used solid-state NMR to investigate the composition of Ziegler-Natta and metallocene catalysts or the interactions between their components.
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Affiliation(s)
- Koen C H Tijssen
- Radboud University, Institute for Molecules and Materials, Heyendaalseweg 135, Nijmegen, The Netherlands.
| | - E S Merijn Blaakmeer
- Radboud University, Institute for Molecules and Materials, Heyendaalseweg 135, Nijmegen, The Netherlands.
| | - Arno P M Kentgens
- Radboud University, Institute for Molecules and Materials, Heyendaalseweg 135, Nijmegen, The Netherlands.
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11
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O’Keefe CA, Johnston KE, Sutter K, Autschbach J, Gauvin R, Trébosc J, Delevoye L, Popoff N, Taoufik M, Oudatchin K, Schurko RW. An Investigation of Chlorine Ligands in Transition-Metal Complexes via 35Cl Solid-State NMR and Density Functional Theory Calculations. Inorg Chem 2014; 53:9581-97. [DOI: 10.1021/ic501004u] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Christopher A. O’Keefe
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario N9B 3P4, Canada
| | - Karen E. Johnston
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario N9B 3P4, Canada
| | - Kiplangat Sutter
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260, United States
| | - Jochen Autschbach
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260, United States
| | - Régis Gauvin
- Université
Lille Nord de France, CNRS UMR8181, Unité de Catalyse et de
Chimie du Solide, UCCS USTL, F-59655 Villeneuve d’Ascq, France
| | - Julien Trébosc
- Université
Lille Nord de France, CNRS UMR8181, Unité de Catalyse et de
Chimie du Solide, UCCS USTL, F-59655 Villeneuve d’Ascq, France
| | - Laurent Delevoye
- Université
Lille Nord de France, CNRS UMR8181, Unité de Catalyse et de
Chimie du Solide, UCCS USTL, F-59655 Villeneuve d’Ascq, France
| | - Nicolas Popoff
- Laboratoire
de Chimie, Catalyse, Polymères et Procédés (UMR-C2P2-5265
CNRS/ESCPE-Lyon/UCBL) ESCPE Lyon, F-308-43, Boulevard du 11 Novembre 1918, F-69616 Villeurbanne Cedex, France
| | - Mostafa Taoufik
- Laboratoire
de Chimie, Catalyse, Polymères et Procédés (UMR-C2P2-5265
CNRS/ESCPE-Lyon/UCBL) ESCPE Lyon, F-308-43, Boulevard du 11 Novembre 1918, F-69616 Villeurbanne Cedex, France
| | - Konstantin Oudatchin
- Steacie Institute for
Molecular Sciences, National Research Council, 100 Sussex Drive, Ottawa, Ontario K1A OR6, Canada
| | - Robert W. Schurko
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario N9B 3P4, Canada
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12
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Bonhomme C, Gervais C, Laurencin D. Recent NMR developments applied to organic-inorganic materials. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2014; 77:1-48. [PMID: 24411829 DOI: 10.1016/j.pnmrs.2013.10.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 10/17/2013] [Indexed: 06/03/2023]
Abstract
In this contribution, the latest developments in solid state NMR are presented in the field of organic-inorganic (O/I) materials (or hybrid materials). Such materials involve mineral and organic (including polymeric and biological) components, and can exhibit complex O/I interfaces. Hybrids are currently a major topic of research in nanoscience, and solid state NMR is obviously a pertinent spectroscopic tool of investigation. Its versatility allows the detailed description of the structure and texture of such complex materials. The article is divided in two main parts: in the first one, recent NMR methodological/instrumental developments are presented in connection with hybrid materials. In the second part, an exhaustive overview of the major classes of O/I materials and their NMR characterization is presented.
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Affiliation(s)
- Christian Bonhomme
- Laboratoire de Chimie de la Matière Condensée de Paris, UMR CNRS 7574, Université Pierre et Marie Curie, Paris 06, Collège de France, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05, France.
| | - Christel Gervais
- Laboratoire de Chimie de la Matière Condensée de Paris, UMR CNRS 7574, Université Pierre et Marie Curie, Paris 06, Collège de France, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05, France
| | - Danielle Laurencin
- Institut Charles Gerhardt de Montpellier, UMR5253, CNRS UM2 UM1 ENSCM, CC1701, Place Eugène Bataillon, 34095 Montpellier Cedex 05, France
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13
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Abstract
Although solid-state NMR (SSNMR) provides rich information about molecular structure and dynamics, the small spin population differences between pairs of spin states that give rise to NMR transitions make it an inherently insensitive spectroscopic technique in terms of signal acquisition. Scientists have continuously addressed this issue via improvements in NMR hardware and probes, increases in the strength of the magnetic field, and the development of innovative pulse sequences and acquisition methodologies. As a result, researchers can now study NMR-active nuclides previously thought to be unobservable or too unreceptive for routine examination via SSNMR. Several factors can make it extremely challenging to detect signal or acquire spectra using SSNMR: (i) low gyromagnetic ratios (i.e., low Larmor frequencies), (ii) low natural abundances or dilution of the nuclide of interest (e.g., metal nuclides in proteins or in organometallic catalysts supported on silica), (iii) inconvenient relaxation characteristics (e.g., very long longitudinal or very short transverse relaxation times), and/or (iv) extremely broad powder patterns arising from large anisotropic NMR interactions. Our research group has been particularly interested in efficient acquisition of broad NMR powder patterns for a variety of spin-1/2 and quadrupolar (spin > 1/2) nuclides. Traditionally, researchers have used the term "wideline" NMR to refer to experiments yielding broad (1)H and (2)H SSNMR spectra ranging from tens of kHz to ∼250 kHz in breadth. With modern FT NMR hardware, uniform excitation in these spectral ranges is relatively easy, allowing for the acquisition of high quality spectra. However, spectra that range in breadth from ca. 250 kHz to tens of MHz cannot be uniformly excited with conventional, high-power rectangular pulses. Rather, researchers must apply special methodologies to acquire such spectra, which have inherently low S/N because the signal intensity is spread across such large spectral breadths. We have suggested the term ultra-wideline NMR (UWNMR) spectroscopy to describe this set of methodologies. This Account describes recent developments in pulse sequences and strategies for the efficient acquisition of UWNMR spectra. After an introduction to anisotropically broadened NMR patterns, we give a brief history of methods used to acquire UWNMR spectra. We then discuss new acquisition methodologies, including the acquisition of CPMG echo trains and the application of pulses capable of broadband excitation and refocusing. Finally, we present several applications of UWNMR methods that use these broadband pulses.
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Affiliation(s)
- Robert W. Schurko
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON, Canada N9B 3P4
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14
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Johnston KE, O'Keefe CA, Gauvin RM, Trébosc J, Delevoye L, Amoureux JP, Popoff N, Taoufik M, Oudatchin K, Schurko RW. A Study of Transition-Metal Organometallic Complexes Combining35Cl Solid-State NMR Spectroscopy and35Cl NQR Spectroscopy and First-Principles DFT Calculations. Chemistry 2013; 19:12396-414. [DOI: 10.1002/chem.201301268] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Indexed: 11/10/2022]
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15
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Lapina OB, Khabibulin DF, Terskikh VV. Multinuclear NMR study of silica fiberglass modified with zirconia. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2011; 39:47-57. [PMID: 21277754 DOI: 10.1016/j.ssnmr.2010.12.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 11/26/2010] [Accepted: 12/22/2010] [Indexed: 05/30/2023]
Abstract
Silica fiberglass textiles are emerging as uniquely suited supports in catalysis, which offer unprecedented flexibility in designing advanced catalytic systems for chemical and auto industries. During manufacturing fiberglass materials are often modified with additives of various nature to improve glass properties. Glass network formers, such as zirconia and alumina, are known to provide the glass fibers with higher strength and to slow down undesirable devitrification processes. In this work multinuclear (1)H, (23)Na, (29)Si, and (91)Zr NMR spectroscopy was used to characterize the effect of zirconia on the molecular-level fiberglass structure. (29)Si NMR results help in understanding why zirconia-modified fiberglass is more stable towards devitrification comparing with pure silica glass. Internal void spaces formed in zirconia-silica glass fibers after acidic leaching correlate with sodium and water distributions in the starting bulk glass as probed by (23)Na and (1)H NMR. These voids spaces are important for stabilization of catalytically active species in the supported catalysts. Potentials of high-field (91)Zr NMR spectroscopy to study zirconia-containing glasses and similarly disordered systems are illustrated.
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Affiliation(s)
- O B Lapina
- Boreskov Institute of Catalysis, Prosp. Lavrentieva 5, Novosibirsk 630090, Russia.
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16
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Liu B, Li Q, Yu M, Liang J, Fan H, Li B. Synthesis of Novel Phenoxyimine Ligands Containing a 2,6-Difluoro-4-Styrylaniline. JOURNAL OF CHEMICAL RESEARCH 2011. [DOI: 10.3184/174751911x12979306434042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
An efficient synthesis of novel phenoxyimine ligands containing a difluorovinylbiphenyl group was based on the Suzuki coupling coupling of 4-bromo-2,6-difluoroaniline with 4-styrylboronic acid followed by a condensation reaction with various arylaldehydes. The structures were established by IR, 1H NMR, 13C NMR spectra and HRMS. The advantages of this synthetic route were its simple operation, mild reaction conditions and good yields.
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Affiliation(s)
- Bin Liu
- State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, P. R. China
- Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China
| | - Qian Li
- Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China
| | - Mingxin Yu
- Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China
| | - Jiaojiao Liang
- State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, P. R. China
| | - Hong Fan
- State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, P. R. China
| | - Bogeng Li
- State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, P. R. China
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