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Bräuniger T, Jansen M. Solid-state NMR Spectroscopy of Quadrupolar Nuclei in Inorganic Chemistry. Z Anorg Allg Chem 2013. [DOI: 10.1002/zaac.201300102] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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2
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Perras FA, Viger-Gravel J, Burgess KMN, Bryce DL. Signal enhancement in solid-state NMR of quadrupolar nuclei. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2013; 51-52:1-15. [PMID: 23336997 DOI: 10.1016/j.ssnmr.2012.11.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2012] [Revised: 11/13/2012] [Accepted: 11/18/2012] [Indexed: 06/01/2023]
Abstract
Recent progress in the development and application of signal enhancement methods for NMR of quadrupolar nuclei in solids is presented. First, various pulse schemes for manipulating the populations of the satellite transitions in order to increase the signal of the central transition (CT) in stationary and rotating solids are evaluated (e.g., double-frequency sweeps, hyperbolic secant pulses). Second, the utility of the quadrupolar Carr-Purcell-Meiboom-Gill (QCPMG) and WURST-QCPMG pulse sequences for the rapid and efficient acquisition of particularly broad CT powder patterns is discussed. Third, less frequently used experiments involving polarization transfer from abundant nuclear spins (cross-polarization) or from unpaired electrons (dynamic nuclear polarization) are assessed in the context of recent examples. Advantages and disadvantages of particular enhancement schemes are highlighted and an outlook on possible future directions for the signal enhancement of quadrupolar nuclei in solids is offered.
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Affiliation(s)
- Frédéric A Perras
- Department of Chemistry, University of Ottawa, Ottawa, Ontario, Canada
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3
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Bräuniger T. Enhancing the central-transition NMR signal of quadrupolar nuclei by spin population transfer using SW-FAM pulse trains with a tangent-shaped sweep profile. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2012; 45-46:16-22. [PMID: 22578791 DOI: 10.1016/j.ssnmr.2012.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 04/20/2012] [Accepted: 04/20/2012] [Indexed: 05/31/2023]
Abstract
Solid-state NMR of quadrupolar nuclei with half-integer spin, such as (25)Mg (I=5/2) or (43)Ca (I=7/2), suffers from low sensitivity, which may be improved using spin population transfer (SPT) from the satellite transitions. Effecting SPT with good efficiency is especially challenging under static conditions, and several techniques such as double-frequency sweeps (DFS), hyperbolic secant pulses (HS) and frequency-swept fast-amplitude modulated pulses (SW-FAM) have been suggested for achieving the necessary manipulations of the satellite transitions. We here investigate the SPT properties of an SW-FAM sequence with a tangent-shaped profile. The new SW(tan)-FAM pulse train is shown to possess superior SPT performance to the SW(1/τ)-FAM sequence, which hitherto has been considered to be the best FAM method for signal enhancement of static spectra, by both numerical simulations on a (27)Al model system, and experimental results on aluminium acetyl acetonate, Al(acac)(3). In addition, the CT enhancement of individual crystallites from the polycrystalline sample with a defined angle between principal z-axis of the diagonal Q-tensor and the external field was considered by numerical simulations. In the vicinity of the magic angle θ(m)=54.7°, a region of zero enhancement exists. Use of the SW(tan)-FAM sequence allows extending the frequency sweep further into this region, with beneficial effects for the overall enhancement and the faithfulness of the line shape. In agreement with previously published studies, our numerical simulations on SPT for single crystals again evidence that the enhancement factors for a polycrystalline sample range from zero enhancement to the maximum gain of 2I, with the total enhancement factor of the full powder pattern being the summation of these strongly varying individual factors. This variation is the cause for line shape distortions in SPT-enhanced spectra. At the same time, these findings prove the capability of frequency sweeps (i.e., DFS and SW-FAM) to fully invert the satellite transitions under certain conditions.
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Affiliation(s)
- Thomas Bräuniger
- Max-Planck-Institut für Festkörperforschung, Stuttgart, Germany.
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4
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Carnevale D, Bodenhausen G. Composite pulses for efficient excitation of half-integer quadrupolar nuclei in NMR of static and spinning solid samples. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.01.058] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Fernandez C, Pruski M. Probing quadrupolar nuclei by solid-state NMR spectroscopy: recent advances. Top Curr Chem (Cham) 2011; 306:119-88. [PMID: 21656101 DOI: 10.1007/128_2011_141] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Solid-state nuclear magnetic resonance (NMR) of quadrupolar nuclei has recently undergone remarkable development of capabilities for obtaining structural and dynamic information at the molecular level. This review summarizes the key achievements attained during the last couple of decades in solid-state NMR of both integer spin and half-integer spin quadrupolar nuclei. We provide a concise description of the first- and second-order quadrupolar interactions, and their effect on the static and magic angle spinning (MAS) spectra. Methods are explained for efficient excitation of single- and multiple-quantum coherences, and acquisition of spectra under low- and high-resolution conditions. Most of all, we present a coherent, comparative description of the high-resolution methods for half-integer quadrupolar nuclei, including double rotation (DOR), dynamic angle spinning (DAS), multiple-quantum magic angle spinning (MQMAS), and satellite transition magic angle spinning (STMAS). Also highlighted are methods for processing and analysis of the spectra. Finally, we review methods for probing the heteronuclear and homonuclear correlations between the quadrupolar nuclei and their quadrupolar or spin-1/2 neighbors.
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6
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Xue X. Determination of J coupling constants between spin-1/2 and quadrupolar nuclei in inorganic solids from spin echo and refocused INEPT experiments: a case study on AlPO₄ berlinite. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2010; 38:62-73. [PMID: 21030218 DOI: 10.1016/j.ssnmr.2010.09.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2010] [Revised: 08/02/2010] [Accepted: 09/14/2010] [Indexed: 05/30/2023]
Abstract
A systematic study utilizing rotor-synchronized homonuclear ((31)P, (27)Al) and heteronuclear ({(31)P}(27)Al and {(27)Al}(31)P) spin echo, and {(27)Al}(31)P refocused INEPT experiments (employing soft pulses for selective excitation of the central transition for the quadrupolar (27)Al (I=5/2)) have been performed on AlPO(4) berlinite at 30 kHz MAS to better understand the J modulation behavior involving half-integer quadrupolar nuclei in solid materials with framework structure. Analyses of the J modulation on either the (27)Al or (31)P coherence in both the {(31)P}(27)Al and {(27)Al}(31)P spin echo experiments, and both periods of the refocused INEPT experiment yield consistent results for the (2)J(AlP) (Al-O-P) coupling constant (ca. 25 Hz). It is noted that the coupling of each (27)Al to four (31)P spins during the first ((27)Al) evolution period of the refocused INEPT, and the populations of (31)P coupled to different numbers (0-4) of (27)Al in the ± 1/2 Zeeman states during (31)P coherence evolution, which have been neglected in previous studies, must be taken into account for proper treatment. Analysis of J modulation on the spin ((27)Al) coupled to spin-1/2 nuclei in general gives more accurate results. Weak long-range homonuclear (4)J(PP) (P-O-Al-O-P) coupling was also observed from the (31)P spin echo and INADEQUATE experiments.
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Affiliation(s)
- Xianyu Xue
- Institute for Study of the Earth's Interior, Okayama University, Yamada 827, Misasa, Tottori 682-0193, Japan.
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7
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Gerothanassis IP. Oxygen-17 NMR spectroscopy: basic principles and applications (part I). PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2010; 56:95-197. [PMID: 20633350 DOI: 10.1016/j.pnmrs.2009.09.002] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Accepted: 09/24/2009] [Indexed: 05/29/2023]
Affiliation(s)
- Ioannis P Gerothanassis
- Section of Organic Chemistry and Biochemistry, Department of Chemistry, University of Ioannina, Ioannina GR-451 10, Greece.
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Cahill L, Hanna J, Wong A, Freitas JC, Yates J, Harris R, Smith M. Natural Abundance25Mg Solid-State NMR of Mg Oxyanion Systems: A Combined Experimental and Computational Study. Chemistry 2009; 15:9785-98. [DOI: 10.1002/chem.200900346] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Rao Y, Kemp TF, Trudeau M, Smith ME, Antonelli DM. 17O and 15N Solid State NMR Studies on Ligand-Assisted Templating and Oxygen Coordination in the Walls of Mesoporous Nb, Ta and Ti Oxides. J Am Chem Soc 2008; 130:15726-31. [DOI: 10.1021/ja8056387] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yuxiang Rao
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Avenue, Windsor, Ontario N9B 3P4, Canada, Department of Physics, University of Warwick, Coventry, U.K., CV4 7AL, and Emerging Technologies, Hydro-Québec Research Institute, 1800 Boulevard Lionel-Boulet, Varennes, Quebec, Canada J3X 1S1
| | - Tom F. Kemp
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Avenue, Windsor, Ontario N9B 3P4, Canada, Department of Physics, University of Warwick, Coventry, U.K., CV4 7AL, and Emerging Technologies, Hydro-Québec Research Institute, 1800 Boulevard Lionel-Boulet, Varennes, Quebec, Canada J3X 1S1
| | - Michel Trudeau
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Avenue, Windsor, Ontario N9B 3P4, Canada, Department of Physics, University of Warwick, Coventry, U.K., CV4 7AL, and Emerging Technologies, Hydro-Québec Research Institute, 1800 Boulevard Lionel-Boulet, Varennes, Quebec, Canada J3X 1S1
| | - Mark E. Smith
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Avenue, Windsor, Ontario N9B 3P4, Canada, Department of Physics, University of Warwick, Coventry, U.K., CV4 7AL, and Emerging Technologies, Hydro-Québec Research Institute, 1800 Boulevard Lionel-Boulet, Varennes, Quebec, Canada J3X 1S1
| | - Dave M. Antonelli
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Avenue, Windsor, Ontario N9B 3P4, Canada, Department of Physics, University of Warwick, Coventry, U.K., CV4 7AL, and Emerging Technologies, Hydro-Québec Research Institute, 1800 Boulevard Lionel-Boulet, Varennes, Quebec, Canada J3X 1S1
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Bräuniger T, Madhu PK. Fast amplitude-modulated pulse trains with frequency sweep (SW-FAM) in solid-state NMR of spin-7/2 nuclei. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2008; 193:102-109. [PMID: 18462964 DOI: 10.1016/j.jmr.2008.04.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Revised: 04/14/2008] [Accepted: 04/15/2008] [Indexed: 05/26/2023]
Abstract
We here investigate the sensitivity enhancement of central-transition NMR spectra of quadrupolar nuclei with spin-7/2 in the solid state, generated by fast amplitude-modulated RF pulse trains with constant (FAM-I) and incremented pulse durations (SW-FAM). Considerable intensity is gained for the central-transition resonance of single-quantum spectra by means of spin population transfer from the satellite transitions, both under static and magic-angle-spinning (MAS) conditions. It is also shown that incorporation of a SW-FAM train into the excitation part of a 7QMAS sequence improves the efficiency of 7Q coherence generation, resulting in improved signal-to-noise ratio. The application of FAM-type pulse trains may thus facilitate faster spectra acquisition of spin-7/2 systems.
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Affiliation(s)
- Thomas Bräuniger
- Institute of Physics, University of Halle, Friedemann-Bach-Platz 6, DE-06108 Halle, Germany.
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Goswami M, Madhu PK. Sensitivity enhancement of the central-transition signal of half-integer spin quadrupolar nuclei in solid-state NMR: features of multiple fast amplitude-modulated pulse transfer. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2008; 192:230-234. [PMID: 18362083 DOI: 10.1016/j.jmr.2008.02.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2008] [Revised: 02/24/2008] [Accepted: 02/26/2008] [Indexed: 05/26/2023]
Abstract
Sensitivity enhancement of solid-state NMR spectrum of half-integer spin quadrupolar nuclei under both magic-angle spinning (MAS) and static cases has been demonstrated by transferring polarisation associated with satellite transitions to the central m=-1/2-->1/2 transition with suitably modulated radio-frequency pulse schemes. It has been shown that after the application of such enhancement schemes, there still remains polarisation in the satellite transitions that can be transferred to the central transition. This polarisation is available without having to wait for the spin system to return to thermal equilibrium. We demonstrate here the additional sensitivity enhancement obtained by making use of this remaining polarisation with fast amplitude-modulated (FAM) pulse schemes under both MAS and static conditions on a spin-3/2 and a spin-5/2 system. Considerable signal enhancement is obtained with the application of the multiple FAM sequence, denoted as m-FAM. We also report here some of the salient features of these multiple FAM sequences with respect to the nutation frequency of the pulses and the spinning frequency.
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Affiliation(s)
- Mithun Goswami
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
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Wong A, Beevers AJ, Kukol A, Dupree R, Smith ME. Solid-state 17O NMR spectroscopy of a phospholemman transmembrane domain protein: implications for the limits of detecting dilute 17O sites in biomaterials. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2008; 33:72-75. [PMID: 18502619 DOI: 10.1016/j.ssnmr.2008.04.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2008] [Indexed: 05/26/2023]
Abstract
The 17O-'diluted' glycine-14 sites in a phospholemman (PLM) transmembrane domain protein are characterized by solid-state 17O NMR spectroscopy. The PLM transmembrane domain is an alpha-helical tetramer unit of four 28-residue peptides and is rigidly embedded in a bilayer where each alpha-helix has an average tilt of 7.3 degrees against the membrane normal. The PLM sample investigated here consists of a high lipid/peptide molar ratio (25:1) with one glycine residue in each helix enriched to <40% (17)O; thus, this is a very dilute 17O-sample and is the most dilute 17O-membrane protein to date to be characterized by solid-state 17O NMR spectroscopy. Based on the spectral analysis of 17O magic angle spinning (MAS) at 14.1 and 18.8T, the PLM transmembrane domain protein consists of multiple crystallographic gly14 sites, suggesting that the tetramer protein is an asymmetric unit with either C2- or C1-rotational symmetry along the bilayer normal.
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Affiliation(s)
- Alan Wong
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
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Kanellopoulos J, Freude D, Kentgens A. A practical comparison of MQMAS techniques. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2007; 32:99-108. [PMID: 17981440 DOI: 10.1016/j.ssnmr.2007.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2007] [Indexed: 05/25/2023]
Abstract
A systematic experimental evaluation of several approaches to multiple-quantum MAS NMR was performed for spin-5/2 nuclei using (27)Al NMR of the aluminosilicate andalusite and the porous aluminum phosphate AlPO(4)-14 as model. Experiments were conducted in the fields of 9.4 and 17.6T using magic-angle spinning frequencies up to 30kHz and rf-field strengths of 250 and 120kHz. Numerical SIMPSON optimizations of the NMR parameters were performed alongside the experimental evaluations. Both theory and experiment show that the optimization is most critical for the species in the sample that have the largest quadrupolar coupling constant. For 5QMAS experiments it could be confirmed that the highest available rf-field strength and rotation frequency are favorable for the efficiency of the experiments. For 3QMAS experiments of sites with moderate quadrupolar coupling constants optimum results were obtained at less stringent conditions. The comparison of a FAM II-modification and DFS gave the expected improvement by a factor of about two with respect to a rectangular pulse. No significant difference between these techniques concerning the signal-to-noise ratios was obtained. An actual improvement of the isotropic resolution by a factor of about two was obtained going from 3QMAS to 5QMAS. In addition the resolution of the spectra increases by a factor of about two going from 9.4 to 17.6T.
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Affiliation(s)
- Johanna Kanellopoulos
- Fakultät für Physik und Geowissenschaften, Universität Leipzig, DE-04103 Leipzig, Germany
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Bräuniger T, Hempel G, Madhu PK. Fast amplitude-modulated pulse trains with frequency sweep (SW-FAM) in static NMR of half-integer spin quadrupolar nuclei. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2006; 181:68-78. [PMID: 16617030 DOI: 10.1016/j.jmr.2006.03.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2006] [Revised: 03/20/2006] [Accepted: 03/21/2006] [Indexed: 05/08/2023]
Abstract
In solid-state NMR of quadrupolar nuclei with half-integer spin I, fast amplitude-modulated (FAM) pulse trains have been utilised to enhance the intensity of the central-transition signal, by transferring spin population from the satellite transitions. In this paper, the signal-enhancement performance of the recently introduced SW-FAM pulse train with swept modulation frequency [T. Bräuniger, K. Ramaswamy, P.K. Madhu, Enhancement of the central-transition signal in static and magic-angle-spinning NMR of quadrupolar nuclei by frequency-swept fast amplitude-modulated pulses, Chem. Phys. Lett. 383 (2004) 403-410] is explored in more detail for static spectra. It is shown that by sweeping the modulation frequencies linearly over the pulse pairs (SW1/tau-FAM), the shape of the frequency distribution is improved in comparison to the original pulse scheme (SWtau-FAM). For static spectra of 27Al (I=5/2), better signal-enhancement performance is found for the SW1/tau-FAM sequence, as demonstrated both by experiments and numerical simulations.
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Affiliation(s)
- Thomas Bräuniger
- Department of Physics, University of Halle, Friedemann-Bach-Platz 6, 06108 Halle, Germany.
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Howes A, Anupõld T, Lemaitre V, Kukol A, Watts A, Samoson A, Smith M, Dupree R. Enhancing resolution and sensitivity of 17O solid-state NMR through combining double rotation, 1H decoupling and satellite modulation for biomolecular applications. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2006.01.061] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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van Beek JD, Dupree R, Levitt MH. Symmetry-based recoupling of 17O-1H spin pairs in magic-angle spinning NMR. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2006; 179:38-48. [PMID: 16309936 DOI: 10.1016/j.jmr.2005.11.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2005] [Revised: 10/31/2005] [Accepted: 11/01/2005] [Indexed: 05/05/2023]
Abstract
We have performed magic-angle-spinning solid-state NMR experiments in which protons are recoupled to oxygen-17 nuclei by applying a symmetry-based recoupling sequence at the proton Larmor frequency. Two-dimensional quadrupole-dipole correlation spectra are produced, in which the second-order quadrupolar shift of the oxygen-17 central transition is correlated with the recoupled heteronuclear dipole-dipole interaction. These spectra are sensitive to the relative orientation of the electric field gradient at the site of the oxygen-17 nucleus and the O-H internuclear vector. We also demonstrate experiments in which polarization is transferred from protons to oxygen-17, and show that oxygen-17 signals may be selected according to the protonation state of the oxygen site. We discuss the small observed value of the heteronuclear dipolar splitting in the central-transition oxygen-17 spectra.
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Affiliation(s)
- Jacco D van Beek
- School of Chemistry, Southampton University, Highfield, Southampton, SO17 1BJ, UK
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Prasad S, Clark TM, Sharma R, Kwak HT, Grandinetti PJ, Zimmermann H. A combined 17O RAPT and MQ-MAS NMR study of L-leucine. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2006; 29:119-24. [PMID: 16293400 DOI: 10.1016/j.ssnmr.2005.10.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2005] [Revised: 10/04/2005] [Indexed: 05/05/2023]
Abstract
We report the application of rotor-assisted population transfer (RAPT) to measure the quadrupolar coupling constant (C(q)) for spin 5/2 nuclei. Results from numerical simulations are presented on the magnitude of enhancement factor as a function of frequency offsets, i.e. the RAPT profile. Experimental O17 RAPT profile is traced for the amino acid L-leucine. In addition, results from MQ-MAS experiments are incorporated to determine the quadrupolar asymmetry parameter (eta(q)). Unlike previous reports, the O17 NMR parameters for an amino acid, L-leucine, is reported at a relatively low field of 9.4 T.
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Affiliation(s)
- Subramanian Prasad
- Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, OH 43210-1173, USA
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Bräuniger T, Madhu PK, Pampel A, Reichert D. Application of fast amplitude-modulated pulse trains for signal enhancement in static and magic-angle-spinning 47,49Ti-NMR spectra. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2004; 26:114-120. [PMID: 15388175 DOI: 10.1016/j.ssnmr.2004.02.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2004] [Revised: 02/19/2004] [Indexed: 05/24/2023]
Abstract
It is demonstrated that the use of fast amplitude-modulated RF pulse trains with constant (FAM-I) and incremented pulse durations (SW-FAM) leads to considerable sensitivity enhancement for the central-transition signal (via spin population transfer from the satellite transitions) for solid-state NMR spectra of titanium, 47Ti (I = [Formula: see text] and 49Ti (I = [Formula: see text]. For the magic-angle spinning spectra of TiO2 and BaTiO3, the intensity of the 49Ti central-transition line was more than doubled compared to simple Hahn-echo acquisition, while for the static case, enhancement factors of 1.6 (TiO2) and 1.8 (BaTiO3) were obtained. No lineshape distortions are observed in either MAS or static spectra of both compounds. Employment of the FAM and SW-FAM sequences should be useful in the routine acquisition of 47,49Ti spectra, as the NMR signal can be detected much faster.
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Affiliation(s)
- Thomas Bräuniger
- Department of Physics NMR Group, University of Halle, Friedemann-Bach-Platz 6, 06108 Halle, Germany.
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Edén M, Grins J, Shen Z, Weng Z. Fast 29Si magic-angle-spinning NMR acquisitions by RAPT-CP 27Al --> 29Si polarization transfer. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2004; 169:279-283. [PMID: 15261623 DOI: 10.1016/j.jmr.2004.05.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2004] [Revised: 05/07/2004] [Indexed: 05/24/2023]
Abstract
Using enhancement of the 27Al central-transition magnetization by applying RAPT prior to 27Al --> 29Si cross-polarization, we demonstrate fast acquisition of 29Si one-dimensional MAS and two-dimensional 27Al-29Si HETCOR spectra on a new sialon phase Ba2Al3Si9N13O5.
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Affiliation(s)
- Mattias Edén
- Physical Chemistry Division, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden.
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Pike KJ, Lemaitre V, Kukol A, Anupõld T, Samoson A, Howes AP, Watts A, Smith ME, Dupree R. Solid-State 17O NMR of Amino Acids. J Phys Chem B 2004. [DOI: 10.1021/jp049958x] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- K. J. Pike
- Departments of Physics and Biological Sciences, University of Warwick, Coventry CV4 7AL, U.K., Biosciences Department, Nestlé Research Centre, Vers-chez-les-Blancs, P.O. Box 44, CH-1000 Lausanne 26, Switzerland, Biochemistry Department, University of Oxford, South Parks Road, Oxford OX1 3QU, U.K., and National Institute for Chemical Physics and Biophysics, Akadeemia Tee 23, Tallinn, Estonia
| | - V. Lemaitre
- Departments of Physics and Biological Sciences, University of Warwick, Coventry CV4 7AL, U.K., Biosciences Department, Nestlé Research Centre, Vers-chez-les-Blancs, P.O. Box 44, CH-1000 Lausanne 26, Switzerland, Biochemistry Department, University of Oxford, South Parks Road, Oxford OX1 3QU, U.K., and National Institute for Chemical Physics and Biophysics, Akadeemia Tee 23, Tallinn, Estonia
| | - A. Kukol
- Departments of Physics and Biological Sciences, University of Warwick, Coventry CV4 7AL, U.K., Biosciences Department, Nestlé Research Centre, Vers-chez-les-Blancs, P.O. Box 44, CH-1000 Lausanne 26, Switzerland, Biochemistry Department, University of Oxford, South Parks Road, Oxford OX1 3QU, U.K., and National Institute for Chemical Physics and Biophysics, Akadeemia Tee 23, Tallinn, Estonia
| | - T. Anupõld
- Departments of Physics and Biological Sciences, University of Warwick, Coventry CV4 7AL, U.K., Biosciences Department, Nestlé Research Centre, Vers-chez-les-Blancs, P.O. Box 44, CH-1000 Lausanne 26, Switzerland, Biochemistry Department, University of Oxford, South Parks Road, Oxford OX1 3QU, U.K., and National Institute for Chemical Physics and Biophysics, Akadeemia Tee 23, Tallinn, Estonia
| | - A. Samoson
- Departments of Physics and Biological Sciences, University of Warwick, Coventry CV4 7AL, U.K., Biosciences Department, Nestlé Research Centre, Vers-chez-les-Blancs, P.O. Box 44, CH-1000 Lausanne 26, Switzerland, Biochemistry Department, University of Oxford, South Parks Road, Oxford OX1 3QU, U.K., and National Institute for Chemical Physics and Biophysics, Akadeemia Tee 23, Tallinn, Estonia
| | - A. P. Howes
- Departments of Physics and Biological Sciences, University of Warwick, Coventry CV4 7AL, U.K., Biosciences Department, Nestlé Research Centre, Vers-chez-les-Blancs, P.O. Box 44, CH-1000 Lausanne 26, Switzerland, Biochemistry Department, University of Oxford, South Parks Road, Oxford OX1 3QU, U.K., and National Institute for Chemical Physics and Biophysics, Akadeemia Tee 23, Tallinn, Estonia
| | - A. Watts
- Departments of Physics and Biological Sciences, University of Warwick, Coventry CV4 7AL, U.K., Biosciences Department, Nestlé Research Centre, Vers-chez-les-Blancs, P.O. Box 44, CH-1000 Lausanne 26, Switzerland, Biochemistry Department, University of Oxford, South Parks Road, Oxford OX1 3QU, U.K., and National Institute for Chemical Physics and Biophysics, Akadeemia Tee 23, Tallinn, Estonia
| | - M. E. Smith
- Departments of Physics and Biological Sciences, University of Warwick, Coventry CV4 7AL, U.K., Biosciences Department, Nestlé Research Centre, Vers-chez-les-Blancs, P.O. Box 44, CH-1000 Lausanne 26, Switzerland, Biochemistry Department, University of Oxford, South Parks Road, Oxford OX1 3QU, U.K., and National Institute for Chemical Physics and Biophysics, Akadeemia Tee 23, Tallinn, Estonia
| | - R. Dupree
- Departments of Physics and Biological Sciences, University of Warwick, Coventry CV4 7AL, U.K., Biosciences Department, Nestlé Research Centre, Vers-chez-les-Blancs, P.O. Box 44, CH-1000 Lausanne 26, Switzerland, Biochemistry Department, University of Oxford, South Parks Road, Oxford OX1 3QU, U.K., and National Institute for Chemical Physics and Biophysics, Akadeemia Tee 23, Tallinn, Estonia
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21
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Hung I, Schurko RW. Solid-State 91Zr NMR of Bis(cyclopentadienyl)dichlorozirconium(IV). J Phys Chem B 2004. [DOI: 10.1021/jp040270u] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ivan Hung
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada N9B 3P4
| | - Robert W. Schurko
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada N9B 3P4
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22
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Siegel R, Nakashima TT, Wasylishen RE. Signal enhancement of NMR spectra of half-integer quadrupolar nuclei in solids using hyperbolic secant pulses. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.03.047] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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23
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Enhancement of the central-transition signal in static and magic-angle-spinning NMR of quadrupolar nuclei by frequency-swept fast amplitude-modulated pulses. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2003.11.049] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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24
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Signal enhancement in NMR spectra of half-integer quadrupolar nuclei via DFS–QCPMG and RAPT–QCPMG pulse sequences. Chem Phys Lett 2003. [DOI: 10.1016/s0009-2614(03)01345-9] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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25
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Madhu PK, Johannessen OG, Pike KJ, Dupree R, Smith ME, Levitt MH. Application of amplitude-modulated radiofrequency fields to the magic-angle spinning NMR of spin-7/2 nuclei. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2003; 163:310-317. [PMID: 12914846 DOI: 10.1016/s1090-7807(03)00159-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We report pulse sequences for the sensitivity enhancement of magic-angle spinning and multiple-quantum magic-angle spinning spectra of spin-72 systems. Sensitivity enhancement is obtained with the use of fast amplitude-modulated (FAM) radiofrequency pulses. In one-dimensional magic-angle spinning experiments, signal enhancement of 3 is obtained by a FAM pulse followed by a soft 90 degrees pulse. In two-dimensional multiple-quantum magic-angle spinning experiments, FAM pulses are used for both the excitation of multiple-quantum coherences and for their conversion into observable single-quantum coherences. The observed signal enhancements are 2.2 in 3Q experiments, 3.1 in 5Q experiments, and 4.1 in 7Q experiments, compared to the conventional two-pulse scheme. The pulse schemes are demonstrated on the 45Sc NMR of Sc2(SO4)3 x 5H2O and the 139La NMR of LaAlO3. We also demonstrate the generation of FAM pulses by double-frequency irradiation.
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Affiliation(s)
- P K Madhu
- Department of Chemistry, University of Southampton, Southampton SO17 1BJ, UK
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