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Optimized multiple quantum MAS lineshape simulations in solid state NMR

William J. Brouwer, Michael C. Davis, Karl T. Mueller
2009 Computer Physics Communications  
In Multiple Quantum Magic Angle Spinning (MQMAS) experiments, a second frequency dimension is created, devoid of quadrupolar anisotropy.  ...  The majority of nuclei available for study in solid state Nuclear Magnetic Resonance have half-integer spin I > 1/2 , with corresponding electric quadrupole moment.  ...  Acknowledgements Jeff Nucciarone and the Research Computing and Cyberinfrastructure group at Penn State are acknowledged for their generous assistance and use of computational resources.  ... 
doi:10.1016/j.cpc.2009.05.012 fatcat:kv2t5odm35gahje35rjejtsrby

Dipolar and Scalar Couplings in Solid State NMR of Quadrupolar Nuclei [chapter]

Alexej Jerschow
2002 Current Developments in Solid State NMR Spectroscopy  
Most NMR-active nuclei found in the periodic table have a quadrupole moment.  ...  This article aims at reviewing how these interactions manifest themselves in quadrupolar NMR and how they can be exploited for resonance assignment and structure elucidation, in spite of the presence of  ...  both in liquid and in solid state NMR today.  ... 
doi:10.1007/978-3-7091-3715-4_1 fatcat:4mq5zowjnbg3rh5uzc7ysxycae

Dipolar and Scalar Couplings in Solid State NMR of Quadrupolar Nuclei

Alexej Jerschow
2002 Chemical Monthly  
Most NMR-active nuclei found in the periodic table have a quadrupole moment.  ...  This article aims at reviewing how these interactions manifest themselves in quadrupolar NMR and how they can be exploited for resonance assignment and structure elucidation, in spite of the presence of  ...  both in liquid and in solid state NMR today.  ... 
doi:10.1007/s00706-002-0497-4 fatcat:mpjaxg77jnao7hkdgkq5iuvrai

24 T High-Resolution and -Sensitivity Solid-State NMR Measurements of Low-Gamma Half-Integer Quadrupolar Nuclei 35Cl and 37Cl

Manoj Kumar PANDEY, Kenjiro HASHI, Shinobu OHKI, Gen NISHIJIMA, Shinji MATSUMOTO, Takashi NOGUCHI, Kenzo DEGUCHI, Atsushi GOTO, Tadashi SHIMIZU, Hideaki MAEDA, Masato TAKAHASHI, Yoshinori YANAGISAWA (+9 others)
2016 Analytical Sciences  
Solid-state NMR observations of low-gamma half-integer quadrupolar nuclei, 35 Cl and 37 Cl, were demonstrated using a 24 T hybrid magnet ( 1 H resonance frequency of 1.02 GHz) comprised of the high-temperature  ...  (HTS) and low-temperature (LTS) superconductors, and compared with results using a 14.1 T standard NMR magnet.  ...  MAS is widely used for most solid-state NMR experiments to remove powder-line broadening resulting from second-rank anisotropic interactions.  ... 
doi:10.2116/analsci.32.1339 pmid:27941265 fatcat:jxqlfzrnm5e6limyjrl2dauemi

Cumulative Subject Index for 1996

1996 Journal of Magnetic Resonance - Series A  
sphere with surface and bulk relaxation, spin-echo measurements, solid-state proton-decoupled 19 F MAS NMR, applications of Blochanalytical solutions and simulations for, KUCHEL, LENNON, AND Siegert  ...  solution, measurement using multiple-quantum edited HNCOCACB experiment, DÖ TSCH, MATSUO, AND WAGNER, NMR spectroscopy, ELIAV AND NAVON, 123A, 32 112B, 95 multiple-quantum NMR, 2D MAS, for removal of  ...  study, EJCHART AND GRYFF-KELLER, 122A, 233 Solids Silicon dioxide biological NMR, multiple-p-pulse sequences in, permutation of phases colloidal, Mn 2/ adsorbed onto, measurement of proton spin-lattice  ... 
doi:10.1006/jmra.1996.0250 fatcat:vkzdf6i4lvbqlg2smwvv2ks3o4

Verdazyl-ribose: A new radical for solid-state dynamic nuclear polarization at high magnetic field

Kent R. Thurber, Thanh-Ngoc Le, Victor Changcoco, David J.R. Brook
2018 Journal of magnetic resonance (San Diego, Calif. 1997 : Print)  
Graphical Abstract Keywords verdazyl; radical; dynamic nuclear polarization; cross-effect mechanism; solid state NMR; magicangle spinning Thurber et al.  ...  Solid-state dynamic nuclear polarization (DNP) using the cross-effect relies on radical pairs whose electron spin resonance (ESR) frequencies differ by the nuclear magnetic resonance (NMR) frequency.  ...  Simulation methods Once we have some information about the solid-state ESR lineshape and relaxation of the verdazyl-ribose radical, we can attempt to gain some insight into its DNP by numerical simulation  ... 
doi:10.1016/j.jmr.2018.02.016 pmid:29501956 pmcid:PMC5856651 fatcat:oxfajcywgbbnzpwgkswgyiolkm

Measuring nitrogen quadrupolar coupling with13C detected wide-line 14N NMR under magic-angle spinning

Zhehong Gan
2008 Chemical Communications  
A 13 C-detected 14 N wide-line NMR experiment is described for measuring nitrogen quadrupolar coupling under magic-angle spinning. This journal is  ...  quadrupolar lineshape (upper curve), (c) first-order 14 N quadrupolar spectra (circles) and simulations (solid line) of two amide nitrogen sites in the natural abundant Ala-Gly-Gly detected via nearby  ...  Quadrupolar coupling parameters C q = 3.48 MHz Z = 0.368 and 10 kHz MAS were used in the simulations.  ... 
doi:10.1039/b716383e pmid:18253531 fatcat:7mi2ltjplvea7ceifqquvtf3bi

Investigating FAM-N pulses for signal enhancement in MQMAS NMR of quadrupolar nuclei

Henri Colaux, Daniel M. Dawson, Sharon E. Ashbrook
2017 Solid State Nuclear Magnetic Resonance  
Although a popular choice for obtaining high-resolution solid-state NMR spectra of quadrupolar nuclei, the inherently low sensitivity of the multiple-quantum magic-angle spinning (MQMAS) experiment has  ...  These include experiments performed under fast MAS, nuclei with higher spin quantum numbers, samples with multiple distinct sites, low-γ nuclei and nuclei subject to large quadrupolar interactions.  ...  The UK 850 MHz solid-state NMR Facility used in this research was funded by EPSRC and BBSRC (contract reference PR140003), as well as the University of Warwick including via part funding through Birmingham  ... 
doi:10.1016/j.ssnmr.2017.01.001 pmid:28131696 fatcat:z4ivc3nwsjbkbb4aectg3kkjli

Sensitivity enhancements in MQ-MAS NMR of spin-5/2 nuclei using modulated rf mixing pulses1Presented in part at the 1st Alpine Conference on Solid-State NMR, September 1999, Chamonix, France.1

Thomas Vosegaard, Dominique Massiot, Philip J. Grandinetti
2000 Chemical Physics Letters  
An X-X pulse train with stepped modulation frequency was employed to enhance the multiple-quantum to single-quan-Ž . tum coherence transfer in the mixing period of the multiple-quantum magic-angle spinning  ...  MQ-MAS experiment for spin I s 5r2 nuclei.  ...  studied by 27 Al solid-state w x NMR 18,28-30 .  ... 
doi:10.1016/s0009-2614(00)00779-x fatcat:geoelir2bzfpbh2r7h4z5zqbuu

Signal Enhancement in the Triple-Quantum Magic-Angle Spinning NMR of Spins-32 in Solids: The FAM–RIACT–FAM Sequence

P.K. Madhu, M.H. Levitt
2002 Journal of magnetic resonance (San Diego, Calif. 1997 : Print)  
We achieve a significant signal enhancement for the triple-quantum magic-angle spinning NMR of a spin-3 2 system, by using an amplitude modulated radiofrequency field, followed by a selective 90 o pulse  ...  The experiment is demonstrated on the 87 Rb NMR of polycrystalline rubidium nitrate.  ...  Introduction The introduction of multiple-quantum magic-angle spinning (MQMAS) [1, 2] has made the high-resolution solid-state NMR of half-integer quadrupolar nuclei routinely feasible.  ... 
doi:10.1006/jmre.2002.2508 pmid:11945045 fatcat:ltlbrw5h5jetbhaznukv4tsiza

Multiple - quantum magic - angle spinning NMR: a new technique for probing quadrupolar nuclei in solids

Ales Medek, Lucio Frydman
1999 Journal of the Brazilian Chemical Society  
We have recently described a new technique capable of recording high resolution NMR spectra of half -integer quadrupolar nuclei in solid samples, based on the combined use of magic -anglespinning (MAS)  ...  and multiple -quantum (MQ) spectroscopy 1 .  ...  The research described in this work was supported by the US National Science Foundation through grants DMR -9806810 and CHE -9841790 (Creativity Extension Award).  ... 
doi:10.1590/s0103-50531999000400003 fatcat:kwe5zkh2ojcjxaqmbfyaeh6pie

Determination of relative tensor orientations by γ-encoded chemical shift anisotropy/heteronuclear dipolar coupling 3D NMR spectroscopy in biological solids

Guangjin Hou, Sivakumar Paramasivam, In-Ja L. Byeon, Angela M. Gronenborn, Tatyana Polenova
2010 Physical Chemistry, Chemical Physics - PCCP  
The effect of the Euler angle α NH on the 2D DIP/CSA lineshapes for the simulated DIP/CSA correlation spectra acquired with the γ-encoded R18 1 7 and R14 2 3/5 pulse sequences.  ...  Supporting Information: The recoupled lineshapes for different crystallite orientations in the laboratory frame produced by γ-encoded R18 1 7 and R14 2 3/5 .  ...  We thank Olga Dmytrenko for help with the DFT calculations, and Lex Vega for multiple discussions.  ... 
doi:10.1039/c0cp00795a pmid:20936218 pmcid:PMC3160241 fatcat:jf7z5nor4raxdpa5iqvlct7gpm

23Na multiple-quantum MAS NMR of the perovskites NaNbO3and NaTaO3

Sharon E. Ashbrook, Laurent Le Pollès, Régis Gautier, Chris J. Pickard, Richard I. Walton
2006 Physical Chemistry, Chemical Physics - PCCP  
The distorted perovskites NaTaO 3 and NaNbO 3 have been studied using 23 Na multiple-quantum (MQ) MAS NMR.  ...  Finally, we discuss the measured NMR parameters in relation to other studies of sodium in high coordination sites in the solid state.  ...  Acknowledgements We thank Dr Stephen Wimperis and Professor Christian Ja¨ger for the use of Bruker Avance spectrometers in Exeter  ... 
doi:10.1039/b604520k pmid:16855721 fatcat:q4qdyfowofgipixttiacyvhk6a

Perspective: Current advances in solid-state NMR spectroscopy

Sharon E. Ashbrook, Paul Hodgkinson
2018 Journal of Chemical Physics  
In contrast to the rapid and revolutionary impact of solution-state NMR on modern chemistry, the field of solid-state NMR has matured more slowly.  ...  This reflects the major technical challenges of much reduced spectral resolution and sensitivity in solid-state as compared to solution-state spectra, as well as the relative complexity of the solid state  ...  -80 kHz) typically used in routine 13 C solid-state NMR.  ... 
doi:10.1063/1.5038547 pmid:30068173 fatcat:xwxtfc5dhzalbim7mmppcvo4ji

PRESTO polarization transfer to quadrupolar nuclei: implications for dynamic nuclear polarization

Frédéric A. Perras, Takeshi Kobayashi, Marek Pruski
2015 Physical Chemistry, Chemical Physics - PCCP  
used CP method, affording more quantitative intensities, improved lineshapes, better sensitivity, and easier optimization.  ...  We show both experimentally and numerically that in experiments involving transfer of magnetization from 1H to the quadrupolar nuclei under MAS, the PRESTO technique consistently outperforms the traditionally  ...  Polarization of quadrupolar spins (S > 1/2) under magic angle spinning (MAS) in the solid-state, however, poses a remarkable challenge to this day. 1 Early attempts at performing cross-polarization (  ... 
doi:10.1039/c5cp04145g pmid:26266874 fatcat:jwbt67mz4bbofn2nszarioedv4
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