Site preferences and ion dynamics in lithium chalcohalide solid solutions with argyrodite structure: II. Multinuclear solid state NMR of the systems Li6PS5−x
                  Se
                     x
                  Cl and Li6PS5−x
                  Se
                     x
                  Br

Abstract A comprehensive multinuclear (7Li, 31P, 35Cl, 77Se, 79Br) nuclear magnetic resonance (NMR) study has been conducted to characterize local structural configurations and atomic distributions in the crystallographically disordered solid solutions of composition Li6PS5−x Se x X (0 ≤ x ≤ 1, X = Cl, Br) with the Argyrodite structure. In contrast to the situation with the corresponding iodide homologs, there is no structural ordering between the 4a and 4c sites, with the halide ions occupying both of them with close to statistical probabilities. Nevertheless, throughout the composition range, the 16e Wyckoff sites of the Argyrodite structure are exclusively occupied by the chalcogen atoms, forming PY4 3− (Y = S, Se) tetrahedra, indicating the absence of P-halogen bonds. 31P magic-angle spinning (MAS)-NMR can serve to differentiate between the various possible PS4−n Se n 3− tetrahedral units in a quantitative fashion. Compared to the case of the anion-ordered Li6PS5−x Se x I solid solutions, the preference of P–S over P–Se bonding is significantly stronger, but it is weaker than in the halide free solid solutions Li7PS6−x Se x . Each individual PS4−n Se n 3− tetrahedron is represented by a peak cluster of up to five resonances, representing the five different configurations in which the PY4 3− ions are surrounded by the four closest chalcogenide and halide anions occupying the 4c sites; this distribution is close to statistical and can be used to deduce deviations of sample compositions from ideal stoichiometry. Non-linear 7Li chemical shift trends as a function of x are interpreted to indicate that the Coulombic traps created by sulfur-rich PS4−n Se n 3− ions (n ≤ 2) within the energy landscape of the lithium ions are deeper than those of the other anionic species present (i.e., selenium-richer PY4 3− tetrahedra, isolated chalcogenide or iodide ions), causing the Li+ ions to spend on average more time near them. Temperature dependent static 7Li NMR linewidths indicate higher mobility in the present systems than in the previously studied Li6PS5−x Se x I solid solutions. Unlike the situation in Li6PS5−x Se x I no rate distinction between intra-cage and inter-cage ionic motion is evident. Lithium ionic mobility increases with increasing selenium content. This effect can be attributed to the influences of higher anionic polarizability and a widening of the lithium ion migration pathways caused by lattice expansion. The results offer interesting new insights into the structure/ionic mobility correlations in this new class of compounds.

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Site preferences and ion dynamics in lithium chalcohalide solid solutions with argyrodite structure: I. A multinuclear solid state NMR study of the system Li6PS5-xSexI and of Li6AsS5I

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2021-3135 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Barbara Koch ◽

Shaio Tong Kong ◽

Özgül Gün ◽

Hans-Jörg Deiseroth ◽

Hellmut Eckert

Keyword(s):

Solid Solutions ◽

Ionic Mobility ◽

Magic Angle Spinning ◽

Magic Angle ◽

Temperature Phase ◽

Lithium Ions ◽

Iodide Ions ◽

Nmr Study ◽

Structural Configurations ◽

Migration Pathways

Abstract A comprehensive multinuclear (7Li, 31P, 75As, 77Se, 127I) NMR study has been conducted to characterize local structural configurations and atomic distributions in the crystallographically ordered solid solutions of composition Li6PS5-x Se x I (0 ≤ x ≤ 1) and in Li6AsS5I. Throughout the composition range, structural ordering between the atoms on the Wyckoff sites 4a and 4c is maintained, with the I− ions exclusively occupying the 4a sites. 31P magic-angle spinning nuclear magnetic resonance (MAS NMR) can serve to differentiate between the various possible PS4-n Se n 3− tetrahedral units in a quantitative fashion, indicating a preference of P-S relative to P-Se bonding. Each individual PS4-n Se n 3− tetrahedron is represented by a peak cluster containing up to five resonances, representing the five different configurations in which the PCh4 3− units are surrounded by the four closest chalcogenide anions occupying the 4c sites; the distribution of S2− and Se2− over these sites is close to statistical. Non-linear 7Li chemical shift trends as a function of x are interpreted to indicate that the Coulombic traps created by sulfur-rich PS4-n Se n 3− ions (n ≥ 2) within the energy landscape of the lithium ions are deeper than those of the other anionic species present (i.e. selenium-richer PCh4 3− tetrahedra, isolated chalcogenide or iodide ions), causing the Li+ ions to spend on average more time near them. Temperature dependent static 7Li NMR linewidths measured on Li6PS5I and Li6AsS5I indicate a two-step motional narrowing process characterized by a clear dynamic distinction between a more rapid localized intra-cage process and a slower, long-range inter-cage process. In the solid solutions this differentiation gradually disappears, leading to an overall increase of lithium ionic mobility with increasing selenium content, which can be attributed to the influences of higher anionic polarizability and a widening of the lithium migration pathways caused by lattice expansion. Furthermore, the low-temperature phase transition in Li6PS5I, which tends to immobilize the lithium ions below 170 K, is suppressed in the solid solutions. The results offer interesting new insights into the -structure/ionic mobility correlations in this new class of compounds.

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The MAS NMR study of solid solutions based on the YAG crystal

Nukleonika ◽

10.1515/nuka-2015-0074 ◽

2015 ◽

Vol 60 (3) ◽

pp. 417-421 ◽

Cited By ~ 1

Author(s):

Bohdan V. Padlyak ◽

Nikolaj A. Sergeev ◽

Marcin Olszewski ◽

Piotr Stępień

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Solid Solutions ◽

Yttrium Aluminum Garnet ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

Nmr Study ◽

Yttrium Aluminum ◽

Angle Spinning

Abstract An 27Al magic angle spinning (MAS) nuclear magnetic resonance (NMR) study of nominally pure and Cr-doped yttrium-aluminum garnet (Y3Al5O12 and Y3Al5O12:Cr) crystals is reported. It has been shown that the doping by Cr of the Y3Al5O12 crystals leads to the variation of the occupation by Al atoms both octahedrally and tetrahedrally coordinated sites of the garnet lattice.

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31P Magic Angle Spinning NMR Study of Flux-Grown Rare-Earth Element Orthophosphate (Monazite/Xenotime) Solid Solutions: Evidence of Random Cation Distribution from Paramagnetically Shifted NMR Resonances

Inorganic Chemistry ◽

10.1021/ic401757z ◽

2013 ◽

Vol 52 (21) ◽

pp. 12605-12615 ◽

Cited By ~ 11

Author(s):

Aaron C. Palke ◽

Jonathan F. Stebbins ◽

Lynn A. Boatner

Keyword(s):

Rare Earth ◽

Rare Earth Element ◽

Solid Solutions ◽

Cation Distribution ◽

Earth Element ◽

Magic Angle Spinning ◽

Magic Angle ◽

Nmr Study ◽

Angle Spinning

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Magic Angle Spinning NMR Study on Inversion Behavior and Vacancy Disorder in Alumina-Rich Spinel

Inorganic Chemistry ◽

10.1021/acs.inorgchem.8b01034 ◽

2018 ◽

Vol 57 (14) ◽

pp. 8390-8395 ◽

Cited By ~ 3

Author(s):

Bingtian Tu ◽

He Zhang ◽

Hao Wang ◽

Weimin Wang ◽

Zhengyi Fu

Keyword(s):

Magic Angle Spinning ◽

Magic Angle ◽

Nmr Study ◽

Angle Spinning

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Phosphorus-31 chemical shieldings in a fused cis-1,2,3-benzothiadiphosphole: a dipolar NMR study

Canadian Journal of Chemistry ◽

10.1139/v92-159 ◽

1992 ◽

Vol 70 (4) ◽

pp. 1229-1235 ◽

Cited By ~ 8

Author(s):

Gang Wu ◽

Roderick E. Wasylishen ◽

William P. Power ◽

Graziano Baccolini

Keyword(s):

Line Shape ◽

Magic Angle Spinning ◽

Pair Approximation ◽

Magic Angle ◽

Single Bond ◽

Chemical Shielding ◽

Spin Pair ◽

Nmr Study ◽

Shielding Tensors ◽

Angle Spinning

Phosphorus-31 NMR static powder spectra and high-resolution magic angle spinning spectra have been obtained for a new heterocyclic compound, cis-2,10-dimethyl[1,2,3]benzothiadiphospholo[2,3b][1,2,3]benzothiadiphosphole (1), which contains a P(III)—P(III) single bond. The homonuclear 31P–31P dipolar interaction manifests itself in both the magic angle spinning spectra and the non-spinning line shape. Under the AX spin pair approximation, analysis of the spinning sidebands in the MAS experiment yields a full characterization of the two 31P chemical shielding tensors. This approximation is confirmed by the exact powder line shape simulation for a homonuclear spin pair. Analysis of the dipolar subspectra also yields the absolute sign of 1J(P,P), which is found to be negative. Keywords: phosphorus–phosphorus single bond, chemical shielding tensors, dipolar NMR, MAS, static line shape.

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Nuclear magnetic resonance (NMR) studies of sintering effects on the lithium ion dynamics in Li1.5Al0.5Ti1.5(PO4)3

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2021-3109 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Edda Winter ◽

Philipp Seipel ◽

Tatiana Zinkevich ◽

Sylvio Indris ◽

Bambar Davaasuren ◽

...

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Lithium Ion ◽

Magic Angle Spinning ◽

Spin Lattice Relaxation ◽

Magic Angle ◽

Nmr Studies ◽

Lithium Ions ◽

Jump Dynamics ◽

Nuclear Magnetic

Abstract Various nuclear magnetic resonance (NMR) methods are combined to study the structure and dynamics of Li1.5Al0.5Ti1.5(PO4)3 (LATP) samples, which were obtained from sintering at various temperatures between 650 and 900 °C. 6Li, 27Al, and 31P magic angle spinning (MAS) NMR spectra show that LATP crystallites are better defined for higher calcination temperatures. Analysis of 7Li spin-lattice relaxation and line-shape changes indicates the existence of two species of lithium ions with clearly distinguishable jump dynamics, which can be attributed to crystalline and amorphous sample regions, respectively. An increase of the sintering temperature leads to higher fractions of the fast lithium species with respect to the slow one, but hardly affects the jump dynamics in either of the phases. Specifically, the fast and slow lithium ions show jumps in the nanoseconds regime near 300 and 700 K, respectively. The activation energy of the hopping motion in the LATP crystallites amounts to ca. 0.26 eV. 7Li field-gradient diffusometry reveals that the long-range ion migration is limited by the sample regions featuring slow transport. The high spatial resolution available from the high static field gradients of our setup allows the observation of the lithium ion diffusion inside the small (<100 nm) LATP crystallites, yielding a high self-diffusion coefficient of D = 2 × 10−12 m2/s at room temperature.

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Solid-state 17O NMR Study of Small Biological Compounds

Zeitschrift für Naturforschung B ◽

10.1515/znb-2007-1111 ◽

2007 ◽

Vol 62 (11) ◽

pp. 1422-1432 ◽

Cited By ~ 8

Author(s):

Kazuhiko Yamada ◽

Tadashi Shimizu ◽

Yoshida Mitsuru ◽

Miwako Asanuma ◽

Masataka Tansho ◽

...

Keyword(s):

Solid State ◽

Magic Angle Spinning ◽

Magic Angle ◽

Multiple Quantum ◽

Peptide Analysis ◽

17O Nmr ◽

Nmr Study ◽

Biological Compounds ◽

Nmr Tensors ◽

Angle Spinning

We present a systematic experimental and theoretical investigation of the oxygen chemical shielding and electric-field-gradient tensors in polycrystalline amino acids and a peptide. Analysis of the 17O magic-angle-spinning (MAS), multiple-quantum MAS, and stationary nuclear magnetic resonance (NMR) spectra yield the magnitudes and the relative orientations between the two NMR tensors. The obtained 17O NMR parameters are sensitive to the hydrogen bond environments. We also demonstrate that solid-state 17O NMR is potentially useful for studying the secondary structures of peptides and proteins.

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