Article

Direct NMR observation of copper-63/65 nuclei in solid K3Cu(CN)4 provides the first experimental example of anisotropic copper chemical shielding. Axially symmetric by virtue of the space group symmetry, the shielding tensor spans 42 ppm, with the greatest shielding when the unique axis is perpendicular to the applied magnetic field. The nuclear quadrupole coupling constant is also appreciable, CQ(63Cu) = -1.125 MHz, reflecting a deviation of the Cu(CN)43- anion from pure tetrahedral symmetry. Spin-spin coupling to 13C nuclei in an isotopically enriched sample is quantified by line-shape simulations of both 13C and 63/65Cu magic-angle spinning (MAS) NMR spectra to be 300 Hz. It is shown that this information is also directly available by 63/65Cu triple-quantum (3Q) MAS NMR. The relative merits of these three approaches to characterizing spin-spin couplings involving half-integer quadrupolar nuclei are discussed. Chemical shielding tensors for nitrogen-15 and carbon-13 are obtained from NMR spectra of non-spinning samples, and are compared to those of tetrahedral group 12 tetracyanometallates. Finally, 2J(63/65Cu,15N) detected in 15N MAS experiments are found to be 19 and 20 Hz for the two crystallographically distinct cyanide ligands.Key words: NMR, quadrupolar nucleus, chemical shielding tensor, multiple-quantum magic-angle spinning, metal cyanide, spin-spin coupling.

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X-ray diffraction and solid-state 119Sn CP-MAS NMR studies of some triaryltin(IV) chlorides

Canadian Journal of Chemistry ◽

10.1139/v03-115 ◽

2003 ◽

Vol 81 (11) ◽

pp. 1187-1195 ◽

Cited By ~ 6

Author(s):

Jordan M Geller ◽

Ian S Butler ◽

Denis FR Gilson ◽

Frederick G Morin ◽

Ivor Wharf ◽

...

Keyword(s):

Solid State ◽

Chemical Shift ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Spin Coupling ◽

Magic Angle ◽

X Ray ◽

Tin Chloride ◽

Angle Spinning ◽

Spin Spin Coupling

The solid-state 119Sn cross-polarization (CP) magic angle spinning (MAS) NMR spectra of a series of triaryltin chlorides of the form Ar3SnCl have been acquired. The indirect spin-spin coupling constants (J(119Sn-35Cl)), quadrupolar-dipolar shifts (d(119Sn-35Cl)), and the 119Sn chemical shift tensors were extracted. For the spectrum of triphenyltin chloride (I) the validity of the first-order perturbation approximation was tested by comparing results of both the perturbation and cubic-equation approaches and a variable-temperature NMR study undertaken to investigate the influence of the previously reported molecular motion in the solid. The X-ray crystal structures of the tris(o-tolyl)tin chloride (II) and tris(p-tolyl)tin chloride (IV) complexes have been examined. They belong to the monoclinic and triclinic space groups P21/n and P[Formula: see text], respectively, which are different from the previously reported tris(m-tolyl)tin chloride (III) complex, which crystallizes in the space group R3 and has threefold molecular symmetry. The structures and NMR properties of the complexes with meta-substituents are quite different from those with ortho- or para-substituents having axially symmetric shift tensors with small spans and larger J values.Key words: aryltin chlorides, magic angle spinning NMR, tin-chlorine spin-spin coupling, 119Sn chemical shift tensor, crystal structure.

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Indirect Spin–Spin Coupling in Multiple-Quantum Magic-Angle-Spinning NMR Spectra of Quadrupolar Nuclei

Journal of Magnetic Resonance ◽

10.1006/jmre.1996.1042 ◽

1997 ◽

Vol 124 (1) ◽

pp. 237-239 ◽

Cited By ~ 27

Author(s):

Gang Wu ◽

Scott Kroeker ◽

Roderick E. Wasylishen ◽

Robert G. Griffin

Keyword(s):

Nmr Spectra ◽

Magic Angle Spinning ◽

Spin Coupling ◽

Magic Angle ◽

Quadrupolar Nuclei ◽

Multiple Quantum ◽

Angle Spinning ◽

Spin Spin Coupling

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Distinction between normal and renal cell carcinoma kidney cortical biopsy samples using pattern recognition of1H magic angle spinning (MAS) NMR spectra

NMR in Biomedicine ◽

10.1002/(sici)1099-1492(200004)13:2<64::aid-nbm612>3.0.co;2-x ◽

2000 ◽

Vol 13 (2) ◽

pp. 64-71 ◽

Cited By ~ 53

Author(s):

A. Rosemary Tate ◽

Peta J. D. Foxall ◽

Elaine Holmes ◽

Detlef Moka ◽

Manfred Spraul ◽

...

Keyword(s):

Renal Cell Carcinoma ◽

Pattern Recognition ◽

Cell Carcinoma ◽

Renal Cell ◽

Nmr Spectra ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

Angle Spinning

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Ultrafast high-resolution magic-angle-spinning NMR spectroscopy

The Analyst ◽

10.1039/c5an00653h ◽

2015 ◽

Vol 140 (12) ◽

pp. 3942-3946 ◽

Cited By ~ 6

Author(s):

Marion André ◽

Martial Piotto ◽

Stefano Caldarelli ◽

Jean-Nicolas Dumez

Keyword(s):

Nmr Spectroscopy ◽

High Resolution ◽

Nmr Spectra ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

Solid Samples ◽

Semi Solid ◽

Angle Spinning

The acquisition of ultrafast high-resolution magic-angle spinning (HR-MAS) NMR spectra of semi-solid samples is demonstrated.

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Two-dimensional MAS–NMR spectra which correlate fast and slow magic angle spinning sideband patterns

Chemical Physics Letters ◽

10.1016/s0009-2614(01)00820-x ◽

2001 ◽

Vol 344 (3-4) ◽

pp. 367-373 ◽

Cited By ~ 35

Author(s):

Charles Crockford ◽

Helen Geen ◽

Jeremy J. Titman

Keyword(s):

Nmr Spectra ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

Two Dimensional ◽

Angle Spinning

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Continuous Flow Hyper-Polarized 129Xe-Mas Nmr Studies of Microporous Materials.

MRS Proceedings ◽

10.1557/proc-775-p3.20 ◽

2003 ◽

Vol 775 ◽

Author(s):

Andrei Nossov ◽

Flavien Guenneau ◽

Marie-Anne Springuel-Huet ◽

Valérie Montouillout ◽

Jean-Pierre Cognec ◽

...

Keyword(s):

Continuous Flow ◽

Nmr Spectra ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

Original Design ◽

Nmr Studies ◽

Powder Samples ◽

Angle Spinning

Summary:A Magic Angle Spinning (MAS) NMR probe has been designed allowing the in-situ measurements of NMR spectra of working catalyst. The probe was built following the original design of M. Hunger [Hunger, 1995 #2]. It allows the magic angle spinning of powder samples up to 3.5 kHz, under gas flowing conditions, and at temperatures up to 573K.

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A multinuclear MAS NMR study of the short-range structure of fluorophosphate glass

Journal of Materials Research ◽

10.1557/jmr.1992.1892 ◽

1992 ◽

Vol 7 (7) ◽

pp. 1892-1899 ◽

Cited By ~ 22

Author(s):

R.K. Brow ◽

Z.A. Osborne ◽

R.J. Kirkpatrick

Keyword(s):

Nmr Spectra ◽

Chemical Shifts ◽

Spectroscopic Studies ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

Nmr Studies ◽

Nmr Study ◽

Fluorophosphate Glass ◽

Angle Spinning

We have examined the bonding arrangements in Na–P–O–F and Na–Al–P–O–F glasses using 19F, 27Al, and 31P solid-state magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy. For the Al-free series of glasses, the 19F NMR spectra are dominated by peaks near +90 ppm, representative of F terminating P-chains. The formation of these bonds has little effect on the 31P chemical shifts, indicating that F preferentially replaces bridging oxygen on the phosphate tetrahedra, consistent with previous NMR studies of crystalline fluorophosphates and other spectroscopic studies of fluorophosphate glass. For the Na–Al–P–O–F glasses, 27Al NMR detects only octahedral Al-sites, the 19F NMR spectra include a second peak near −12 ppm due to F bonded to Al, and the 31P NMR spectra contain signals due to Q1-sites with one or more Al next-nearest neighbors. The relative intensity of the two 19F peaks correlates well with previous spectroscopic studies and shows that a greater fraction of F–P bonds forms when the base glass is remelted in NH4HF2.

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HR-MAS NMR Applications in Plant Metabolomics

Molecules ◽

10.3390/molecules26040931 ◽

2021 ◽

Vol 26 (4) ◽

pp. 931

Author(s):

Dieuwertje Augustijn ◽

Huub J. M. de Groot ◽

A. Alia

Keyword(s):

Metabolic Profile ◽

Nmr Spectra ◽

Pulse Sequences ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

Plant Metabolomics ◽

Extraction Step ◽

Angle Spinning ◽

Processing Steps

Metabolomics is used to reduce the complexity of plants and to understand the underlying pathways of the plant phenotype. The metabolic profile of plants can be obtained by mass spectrometry or liquid-state NMR. The extraction of metabolites from the sample is necessary for both techniques to obtain the metabolic profile. This extraction step can be eliminated by making use of high-resolution magic angle spinning (HR-MAS) NMR. In this review, an HR-MAS NMR-based workflow is described in more detail, including used pulse sequences in metabolomics. The pre-processing steps of one-dimensional HR-MAS NMR spectra are presented, including spectral alignment, baseline correction, bucketing, normalisation and scaling procedures. We also highlight some of the models which can be used to perform multivariate analysis on the HR-MAS NMR spectra. Finally, applications of HR-MAS NMR in plant metabolomics are described and show that HR-MAS NMR is a powerful tool for plant metabolomics studies.

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Distribution of water in the pores of periodic mesoporous organosilicates – a proton solid state MAS NMR study

Physical Chemistry Chemical Physics ◽

10.1039/c8cp04902e ◽

2018 ◽

Vol 20 (46) ◽

pp. 29351-29361 ◽

Cited By ~ 3

Author(s):

V. S. Veena ◽

Kavya Illath ◽

Anish Lazar ◽

C. P. Vinod ◽

T. G. Ajithkumar ◽

...

Keyword(s):

Solid State ◽

Nmr Spectra ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

Pore Filling ◽

Nmr Study ◽

Proposed Model ◽

Water Layers ◽

Angle Spinning

Proposed model of water layers and pore filling in ethane substituted periodic mesoporous organosilicates (PMOE) based on analysis of solid state magic angle spinning (MAS) proton NMR spectra.

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