Measurement of quadrupolar coupling constants, shielding tensor elements and the relative orientation of quadrupolar and shielding tensor principal axis systems for rubidium-87 and rubidium-85 nuclei in rubidium salts by solid-state NMR

1990 ◽  
Vol 94 (2) ◽  
pp. 553-561 ◽  
Author(s):  
John T. Cheng ◽  
John C. Edwards ◽  
Paul D. Ellis
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
Principal Axis ◽  
Relative Orientation ◽  
Coupling Constants ◽  
Quadrupolar Coupling ◽  
Shielding Tensor

Structural analysis of lanthanum-containing battery materials using 139La solid-state NMR

2011 ◽  
Vol 89 (9) ◽  
pp. 1105-1117 ◽  
Author(s):  
Leigh Spencer ◽  
Eric Coomes ◽  
Eric Ye ◽  
Victor Terskikh ◽  
Adam Ramzy ◽  
...  
Keyword(s):  
Solid State ◽  
Structural Analysis ◽  
Lithium Ion Battery ◽  
Solid State Nmr ◽  
Nmr Spectra ◽  
Lithium Ion ◽  
Atomic Level ◽  
Coupling Constants ◽  
Battery Materials ◽  
Quadrupolar Coupling

139La solid-state NMR spectra, acquired at 21.1 and 11.7 T, have been used to evaluate the structural properties of the lithium ion battery materials, La32Li16Fe6.4O67 and Li3xLa2/3–xTiO3. In particular, atomic-level disorder in the second coordination sphere environment of lanthanum in these materials has been indicated by the observation of a distribution in the asymmetry parameters and the quadrupolar coupling constants derived from experimental NMR spectra, and supported by theoretical calculations. For comparison, 139La NMR has been obtained for the two model compounds La2O3 and LaNbO4, in which there is no atomic-level disorder. Quadrupolar coupling constants in the range of 17 to 59 MHz have been measured, and these values are supported by previous work as well as theoretical predictions performed in CASTEP. It has been shown that 139La NMR is a useful tool for the structural analysis of lithium ion battery materials, and when combined with 7Li MAS NMR and powder X-ray diffraction, can be used to determine the structure of complex solid-state electrolyte and electrode materials.

A solid state NMR and molecular orbital study of hydroxylammonium chloride

1999 ◽  
Vol 77 (11) ◽  
pp. 1813-1820 ◽  
Author(s):  
Glenn H Penner ◽  
YC Phillis Chang ◽  
H Michelle Grandin
Keyword(s):  
Activation Energy ◽  
Solid State ◽  
Chemical Shift ◽  
Molecular Orbital ◽  
Solid State Nmr ◽  
Coupling Constants ◽  
Basis Sets ◽  
Exponential Factor ◽  
Line Shapes ◽  
Quadrupolar Coupling

Deuterium and nitrogen-15 NMR spectroscopy has been used to measure the 2H quadrupolar coupling and 15N chemical shift tensors in solid hydroxylammonium chloride, NH3OH+Cl-, (HAC). In addition, the NH3 and OH dynamics have been investigated by variable temperature 2H line shapes and T1 measurements. The Arrhenius activation energy for NH3 rotation is 22.5 ± 1.8 kJ/mol with a pre-exponential factor of 8 ± 3 × 1012 s-1 from line shapes and 21.3 ± 2 kJ/mol with an infinite temperature correlation time, τinf,, of 5.0 ± 0.4 × 10-14 s from the T1 analysis. The latter value corresponds to a pre-exponential factor of 6.7 ± 0.5 × 1012 s-1, if a three-site exchange is assumed. There was no evidence for OH reorientation up to 405 K, indicating a rather strong OH···Cl hydrogen bond. Previously reported inconsistencies between crystal structure and molecular orbital derived N-O bond lengths are cleared up by performing geometry optimizations with large basis sets and taking electron correlation into account. The internal rotational potential for the isolated HA cation is calculated to be 5.8 kJ/mol at the MP2/6-31G** level, with the trans geometry preferred. Calculations that employ the neutron diffraction geometry and include the Cl- anions that surround the HA+ cation yield an upper limit for the activation energy for NH3 group rotation of 62 kJ/mol. Analysis of the deuterium spectrum and T1 data yield nuclear quadrupolar coupling constants of 160 ± 5 kHz and 194 ± 5 kHz (η = 0.50 ± 0.05) for the ND3 and OD deuterons, respectively. Density functional calculations of the deuterium and nitrogen-14 nuclear quadrupolar coupling constants at the B3LYP level show that it is necessary to include the influence of the surrounding chloride anions. We have also shown that it is possible to obtain accurate proton chemical shifts from the deuterium MAS spectrum of solid HAC-d4.Key words: solid state NMR, molecular dynamics, nitrogen 15 chemical shift anisotropy.

Probing solid iminobis(diorganophosphine chalcogenide) systems with multinuclear magnetic resonance

2009 ◽  
Vol 87 (1) ◽  
pp. 348-360 ◽  
Author(s):  
Bryan A Demko ◽  
Roderick E Wasylishen
Keyword(s):  
Solid State ◽  
Chemical Shift ◽  
Solid State Nmr ◽  
Magnetic Shielding ◽  
Chemical Shift Tensors ◽  
X Ray ◽  
X Ray Crystallography ◽  
Shielding Tensor ◽  
Nuclear Magnetic Shielding Tensors ◽  
Nuclear Magnetic

A 31P and 77Se solid-state NMR investigation of the iminobis(diorganophosphine chalcogenide) HN(R2PE)2 (R = Ph,iPr; E = O, S, Se) systems is presented. The NMR results are discussed in terms of the known HN(R2PE)2 structures available from X-ray crystallography. The phosphorus chemical shift tensors are found to be sensitive to the nature of the alkyl and chalcogen substituents. The nature of the R group also influences the selenium chemical shift tensors of HN(R2PSe)2 (R = Ph, iPr), which are shown to be sensitive to hydrogen bonding in the dimer structure of HN(Ph2PSe)2 and to the presence of disorder in the case of HN(iPr2PSe)2. Scalar relativistic ZORA DFT nuclear magnetic shielding tensor calculations were performed yielding the orientations of the corresponding chemical shift tensors. A theoretical investigation into the effect of the E-P···P-E “torsion” angle on the phosphorus and selenium chemical shift tensors of a truncated HN(Me2PSe)2 system indicates that the electronic effect of the alkyl group on the respective nuclear magnetic shielding tensors are more important than the steric effect of the E-P···P-E torsion angle.Key words: iminobis(diorganophosphine chalcogenide), solid-state NMR, 31P NMR, 77Se NMR, ZORA DFT.

A solid-state NMR investigation of the colossal expansion material, Ag3Co(CN)6

2012 ◽  
Vol 90 (10) ◽  
pp. 891-901 ◽  
Author(s):  
Brett C. Feland ◽  
Guy M. Bernard ◽  
Roderick E. Wasylishen
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
Negative Thermal Expansion ◽  
Coupling Constant ◽  
Quadrupolar Coupling Constant ◽  
Quadrupolar Coupling ◽  
Field Gradients ◽  
Increasing Temperature ◽  
Nmr Properties ◽  
Expansion Behaviour

Presented here is a solid-state NMR investigation of the so-called “colossal expansion” material, Ag3Co(CN)6, a compound that exhibits some of the largest positive and negative thermal expansion properties reported. This study explores the 13C, 15N, and 59Co NMR properties of this material at room temperature and at variable temperatures with the goal of probing the effects of this colossal expansion behaviour on these properties. We found that the flexible nature of the crystal framework leads to a distribution of electric field gradients, and that, oddly enough, no strong correlation is observed between the NMR parameters of Ag3Co(CN)6 and its colossal expansion nature. The 59Co isotropic chemical shift increased and the 59Co nuclear quadrupolar coupling constant decreased with increasing temperature, but neither of these relationships were extraordinary when compared to other octahedral Co(III) complexes. The link between the colossal expansion and the NMR properties of Ag3Co(CN)6 may be the distribution of lattice parameters and hence unusually broad features in the 59Co NMR spectra. The high order of symmetry at the cobalt site resulted in a small quadrupolar coupling constant less than 1 MHz in magnitude. We also observed a |1J(107/109Ag,15N)| value of 96 Hz, the largest 107/109Ag–15N coupling constant reported to date.

scholarly journals Spying on the boron–boron triple bond using spin–spin coupling measured from 11B solid-state NMR spectroscopy

2015 ◽  
Vol 6 (6) ◽  
pp. 3378-3382 ◽  
Author(s):  
Frédéric A. Perras ◽  
William C. Ewing ◽  
Theresa Dellermann ◽  
Julian Böhnke ◽  
Stefan Ullrich ◽  
...  
Keyword(s):  
Solid State ◽  
Nmr Spectroscopy ◽  
Solid State Nmr ◽  
Triple Bond ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Solid State Nmr Spectroscopy ◽  
Spin Spin Coupling ◽  
Insight Into

Boron–boron J coupling constants provide new insight into the nature of the boron–boron triple bond.

scholarly journals Linear dicoordinate beryllium: a 9Be solid-state NMR study of a discrete zero-valent s-block beryllium complex

2018 ◽  
Vol 96 (7) ◽  
pp. 646-652 ◽  
Author(s):  
C. Leroy ◽  
J.K. Schuster ◽  
T. Schaefer ◽  
K. Müller-Buschbaum ◽  
H. Braunschweig ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Chemical Shift ◽  
Solid State Nmr ◽  
Chemical Shift Tensor ◽  
X Ray Diffraction ◽  
X Ray ◽  
Quadrupolar Coupling ◽  
Nmr Study ◽  
Tensor Data

Beryllium-9 (9Be) quadrupolar coupling and chemical shift tensor data are reported for bis(1-(2,6-diisopropylphenyl)-3,3,5,5-tetramethylpyrrolidine-2-ylidene)beryllium (Be(CAAC)2). These are the first such data for beryllium in a linear dicoordinate environment. The 9Be quadrupolar coupling constant, 2.36(0.02) MHz, is the largest recorded in the solid state to date for this isotope. The span of the beryllium chemical shift tensor, 22(2) ppm, covers about half of the known 9Be chemical shift range, and the isotropic 9Be chemical shift, 32.0(0.3) ppm, is the largest reported in the solid state to our knowledge. DFT calculations reproduce the experimental data well. A natural localized molecular orbital approach has been used to explain the origins and orientation of the beryllium electric field gradient tensor. The single-crystal X-ray structure of a second polymorph of Be(CAAC)2 is also reported. Inspection of the powder X-ray diffraction data shows that the new crystal structure is part of the bulk product next to another crystalline phase. Therefore, experimental X-ray powder data for the microcrystalline powder sample and the SSNMR data do not fully match either the originally reported crystal structure (Arrowsmith et al. Nat. Chem. 2016, 8, 890–894) or the new polymorph. The ability of solid-state NMR and powder X-ray diffraction to characterize powdered samples was thus particularly useful in this work.

scholarly journals 14N, 13C, and 119Sn solid-state NMR characterization of tin(II) carbodiimide Sn(NCN)

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Aleksander Jaworski ◽  
Jędrzej Piątek ◽  
Liuda Mereacre ◽  
Cordula Braun ◽  
Adam Slabon
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
Chemical Shifts ◽  
Magic Angle Spinning ◽  
Magic Angle ◽  
Quadrupolar Coupling ◽  
Nmr Study ◽  
Nmr Characterization ◽  
Angle Spinning ◽  
High Level

Abstract We report the first magic-angle spinning (MAS) nuclear magnetic resonance (NMR) study on Sn(NCN). In this compound the spatially elongated (NCN)2− ion is assumed to develop two distinct forms: either cyanamide (N≡C–N2−) or carbodiimide (−N=C=N−). Our 14N MAS NMR results reveal that in Sn(NCN) the (NCN)2− groups exist exclusively in the form of symmetric carbodiimide ions with two equivalent nitrogen sites, which is in agreement with the X-ray diffraction data. The 14N quadrupolar coupling constant | C Q | $\vert {C}_{\text{Q}}\vert $  ≈ 1.1 MHz for the −N=C=N− ion in Sn(NCN) is low when compared to those observed in molecular compounds that comprise cyano-type N≡C– moieties ( | C Q | $\vert {C}_{\text{Q}}\vert $  > 3.5 MHz). This together with the information from 14N and 13C chemical shifts indicates that solid-state NMR is a powerful tool for providing atomic-level insights into anion species present in these compounds. The experimental NMR results are corroborated by high-level calculations with quantum chemistry methods.

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