Solid state nuclear magnetic resonance最新文献_第2页

Solid-state NMR spectra of amino acid enantiomers and their relative intensities 氨基酸对映体的固态 NMR 光谱及其相对强度

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2024-04-01 DOI: 10.1016/j.ssnmr.2024.101925

Audrey-Anne Lafrance, Manon Girard, David L. Bryce

{"title":"Solid-state NMR spectra of amino acid enantiomers and their relative intensities","authors":"Audrey-Anne Lafrance, Manon Girard, David L. Bryce","doi":"10.1016/j.ssnmr.2024.101925","DOIUrl":"10.1016/j.ssnmr.2024.101925","url":null,"abstract":"<div>Under normal experimental conditions in an achiral environment, NMR spectra of enantiomers have chemical shifts and J couplings which are not differentiable. In this work, the reproducibility of spectral intensities for pairs of amino acid enantiomers, as well as factors influencing these intensities, is assessed using 13C and 15N cross-polarization magic-angle spinning (CP/MAS) NMR spectroscopy. Prompted by a recent literature debate over a possible influence of the chirality-induced spin selectivity (CISS) effect on spectral intensities obtained in CP/MAS NMR experiments carried out on enantiomers, a number of control experiments were performed with recycle delays of at least 5T1. These included the analysis of proton-decoupled Bloch decay solid-state NMR spectra as well as solution NMR spectra where the cross polarization process is absent. Bloch decay and CP/MAS NMR spectra yield the same relative intensities for pairs of enantiomers while solution NMR spectra provide relative intensities closest to unity. Differences of plus-or-minus a few percent in the D/L spectral intensity ratios observed in all solid-state NMR experiments are due to sample preparation (i.e., grinding, particle size, partial amorphization) and limitations on sample purity. As previously described in the literature, more drastic intensity differences on the order of 50% are easily created by ball milling the samples. Finally, apodization is shown to invert the apparent D/L ratio in low signal-to-noise 15N CP/MAS NMR spectra of aspartic acid enantiomers. In summary, no spectral intensity differences attributable to enantiomerism are identified.</div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0926204024000110/pdfft?md5=14550f94457b1ce258b7efffa00efb7e&pid=1-s2.0-S0926204024000110-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140349354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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14N NMR of magnetically oriented microcrystals 磁定向微晶的 14N NMR

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2024-03-26 DOI: 10.1016/j.ssnmr.2024.101924

Tomoya Kamide, Yasuto Noda, Kazuyuki Takeda

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Double-rotation (DOR) NMR spectroscopy: Progress and perspectives 双旋转 (DOR) NMR 光谱：进展与展望

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2024-03-06 DOI: 10.1016/j.ssnmr.2024.101923

David L. Bryce

{"title":"Double-rotation (DOR) NMR spectroscopy: Progress and perspectives","authors":"David L. Bryce","doi":"10.1016/j.ssnmr.2024.101923","DOIUrl":"10.1016/j.ssnmr.2024.101923","url":null,"abstract":"<div>Double-rotation (DOR) solid-state NMR spectroscopy is a high-resolution technique developed in the late 1980s. Although multiple-quantum magic-angle spinning (MQMAS) became the most widely used high-resolution method for half-integer spin quadrupoles after 1995, development and application of DOR NMR to a variety of chemical and materials science problems has endured. This Trend article recapitulates the development of DOR NMR, discusses various applications, and describes possible future directions. The main technical limitations specific to DOR NMR are simply related to the size of the double rotor system. The relatively large outer rotor (and thus coil) used for most applications over the past 35 years translates into relatively low rotor spinning frequencies, a low filling factor, and weak radiofrequency powers available for excitation and for proton decoupling. Ongoing developments in NMR instrumentation, including ever-shrinking MAS rotors and spherical NMR rotors, could solve many of these problems and may augur a renaissance for DOR NMR.</div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0926204024000092/pdfft?md5=4bf8aebce516887aad8eff41ae32bdb9&pid=1-s2.0-S0926204024000092-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140057932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Carbon-detected deuterium solid-state NMR rotating frame relaxation measurements for protein methyl groups under magic angle spinning 碳检测氘固态核磁共振旋转框架弛豫测量魔角旋转下的蛋白质甲基基团

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2024-02-22 DOI: 10.1016/j.ssnmr.2024.101922

Liliya Vugmeyster , Dmitry Ostrovsky , Riqiang Fu

{"title":"Carbon-detected deuterium solid-state NMR rotating frame relaxation measurements for protein methyl groups under magic angle spinning","authors":"Liliya Vugmeyster , Dmitry Ostrovsky , Riqiang Fu","doi":"10.1016/j.ssnmr.2024.101922","DOIUrl":"10.1016/j.ssnmr.2024.101922","url":null,"abstract":"<div>Deuterium rotating frame solid-state NMR relaxation measurements (2H <math><mrow><msub><mi>R</mi><mrow><mn>1</mn><mi>ρ</mi></mrow></msub></mrow></math>) are important tools in quantitative studies of molecular dynamics. We demonstrate how 2H to 13C cross-polarization (CP) approaches under 10–40 kHz magic angle spinning rates can be combined with the 2H <math><mrow><msub><mi>R</mi><mrow><mn>1</mn><mi>ρ</mi></mrow></msub></mrow></math> blocks to allow for extension of deuterium rotating frame relaxation studies to methyl groups in biomolecules. This extension permits detection on the 13C nuclei and, hence, for the achievement of site-specific resolution. The measurements are demonstrated using a nine-residue low complexity peptide with the sequence GGKGMGFGL, in which a single selective −13CD3 label is placed at the methionine residue. Carbon-detected measurements are compared with the deuterium direct-detection results, which allows for fine-tuning of experimental approaches. In particular, we show how the adiabatic respiration CP scheme and the double adiabatic sweep on the 2H and 13C channels can be combined with the 2H <math><mrow><msub><mi>R</mi><mrow><mn>1</mn><mi>ρ</mi></mrow></msub></mrow></math> relaxation rates measurement. Off-resonance 2H <math><mrow><msub><mi>R</mi><mrow><mn>1</mn><mi>ρ</mi></mrow></msub></mrow></math> measurements are investigated in addition to the on-resonance condition, as they extent the range of effective spin-locking field.</div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139937507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

NMR crystallography of amino acids 氨基酸的核磁共振晶体学

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2024-02-19 DOI: 10.1016/j.ssnmr.2024.101921

Ema Chaloupecká , Václav Tyrpekl , Kateřina Bártová , Yusuke Nishiyama , Martin Dračínský

{"title":"NMR crystallography of amino acids","authors":"Ema Chaloupecká , Václav Tyrpekl , Kateřina Bártová , Yusuke Nishiyama , Martin Dračínský","doi":"10.1016/j.ssnmr.2024.101921","DOIUrl":"10.1016/j.ssnmr.2024.101921","url":null,"abstract":"<div>The development of NMR crystallography methods requires a reliable database of chemical shifts measured for systems with known crystal structure. We measured and assigned carbon and hydrogen chemical shifts of twenty solid natural amino acids of known polymorphic structure, meticulously determined using powder X-ray diffraction. We then correlated the experimental data with DFT-calculated isotropic shieldings. The small size of the unit cell of most amino acids allowed for advanced computations using various families of DFT functionals, including generalized gradient approximation (GGA), meta-GGA and hybrid DFT functionals. We tested several combinations of functionals for geometry optimizations and NMR calculations. For carbon shieldings, the widely used GGA functional PBE performed very well, although an improvement could be achieved by adding shielding corrections calculated for isolated molecules using a hybrid functional. For hydrogen nuclei, we observed the best performance for NMR calculations carried out with structures optimized at the hybrid DFT level. The high fidelity of the calculations made it possible to assign additional signals that could not be assigned based on experiments alone, for example signals of two non-equivalent molecules in the unit cell of some of the amino acids.</div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139916929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Development of in situ high resolution NMR: Proof-of-principle for a new (spinning) cylindrical mini-pellet approach applied to a Lithium ion battery 原位高分辨率核磁共振的开发：应用于锂离子电池的新型（旋转）圆柱形微型颗粒方法的原理验证

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2023-12-18 DOI: 10.1016/j.ssnmr.2023.101914

Irshad Mohammad , Musa Ali Cambaz , Ago Samoson , Maximilian Fichtner , Raiker Witter

{"title":"Development of in situ high resolution NMR: Proof-of-principle for a new (spinning) cylindrical mini-pellet approach applied to a Lithium ion battery","authors":"Irshad Mohammad , Musa Ali Cambaz , Ago Samoson , Maximilian Fichtner , Raiker Witter","doi":"10.1016/j.ssnmr.2023.101914","DOIUrl":"10.1016/j.ssnmr.2023.101914","url":null,"abstract":"<div>Solid-state nuclear magnetic resonance (ssNMR) spectroscopy is a powerful technique for characterizing the local structure and dynamics of battery and other materials. It has been widely used to investigate bulk electrode compounds, electrolytes, and interfaces. Beside common ex situ investigations, in situ and operando techniques have gained considerable importance for understanding the reaction mechanisms and cell degradation of electrochemical cells.Herein, we present the recent development of in situ magic angle spinning (MAS) NMR methodologies to study batteries with high spectral resolution, setting into context possible advances on this topic. A mini cylindrical cell type insert for 4 mm MAS rotors is introduced here, being demonstrated on a Li/VO2F electrochemical system, allowing the acquisition of high-resolution 7Li MAS NMR spectra, spinning the electrochemical cell up to 15 kHz.</div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138740138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Field-stepwise-swept solid-state 127I NMR of 1,4-diiodobenzene 1,4-二碘苯的场逐步扫描固态127I核磁共振。

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2023-12-01 DOI: 10.1016/j.ssnmr.2023.101905

Kazuhiko Yamada , Tatsuo Kaiho

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Kinetics of 1H →31P NMR cross-polarization and dynamics in a layered crystalline α-Sn(IV) phosphate α-Sn(IV)磷酸层状晶体的1H→31P核磁共振交叉极化动力学及动力学

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2023-10-01 DOI: 10.1016/j.ssnmr.2023.101898

Vladimir I. Bakhmutov, Douglas W. Elliott, Hong-Cai Zhou

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Solid-state NMR of organic molecules: Characterising solid-state form 有机分子的固态核磁共振:表征固态形式

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2023-08-01 DOI: 10.1016/j.ssnmr.2023.101876

Steven P. Brown, Yongchao Su

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High resolution solid-state NMR on the desktop 高分辨率固态核磁共振在桌面上

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2023-08-01 DOI: 10.1016/j.ssnmr.2023.101884

Ke Xu , Fettah Aldudak , Oliver Pecher , Marco Braun , Andreas Neuberger , Holger Foysi , Jörn Schmedt auf der Günne

{"title":"High resolution solid-state NMR on the desktop","authors":"Ke Xu , Fettah Aldudak , Oliver Pecher , Marco Braun , Andreas Neuberger , Holger Foysi , Jörn Schmedt auf der Günne","doi":"10.1016/j.ssnmr.2023.101884","DOIUrl":"10.1016/j.ssnmr.2023.101884","url":null,"abstract":"<div>High-resolution low-field nuclear magnetic resonance (NMR) spectroscopy has found wide application for characterization of liquid compounds because of the low maintenance cost of modern permanent magnets. Solid-state NMR so far is limited to low-resolution measurements of static powders, because of the limited space available in this type of magnet. Magic-angle sample spinning and low-magnetic fields are an attractive combination to achieve high spectral resolution especially for paramagnetic solids. Here we show that magic angle spinning modules can be miniaturized using 3D printing techniques so that high-resolution solid-state NMR in permanent magnets becomes possible. The suggested conical rotor design was developed using finite element calculations and provides sample spinning frequencies higher than 20 kHz. The setup was tested on various diamagnetic and paramagnetic compounds including paramagnetic battery materials. The only comparable experiments in low-cost magnets known so far, had been done in the early times of magic angle spinning using electromagnets at much lower sample spinning frequency. Our results demonstrate that high-resolution low-field magic-angle-spinning NMR does not require expensive superconducting magnets and that high-resolution solid-state NMR spectra of paramagnetic compounds are feasible. Generally, this could introduce low-field solid-state NMR for abundant nuclei standard as a routine analytical tool.</div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9982675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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