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

A Numerical simulation method for analyzing 1H spin diffusion NMR for Multicomponent and multiphase polymer systems 分析多组分和多相聚合物系统 1H 自旋扩散 NMR 的数值模拟方法

IF 1.8 3区化学

Solid state nuclear magnetic resonance Pub Date : 2024-06-26 DOI: 10.1016/j.ssnmr.2024.101946

Xuran Jin , Wei Chen

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A combined solid-state 1H, 13C, 17O NMR and periodic DFT study of hyperfine coupling tensors in paramagnetic copper(II) compounds 顺磁铜（II）化合物中超细耦合张量的固态 1H、13C、17O NMR 和周期 DFT 综合研究。

IF 1.8 3区化学

Solid state nuclear magnetic resonance Pub Date : 2024-06-25 DOI: 10.1016/j.ssnmr.2024.101945

Yizhe Dai , Victor Terskikh , Gang Wu

{"title":"A combined solid-state 1H, 13C, 17O NMR and periodic DFT study of hyperfine coupling tensors in paramagnetic copper(II) compounds","authors":"Yizhe Dai , Victor Terskikh , Gang Wu","doi":"10.1016/j.ssnmr.2024.101945","DOIUrl":"10.1016/j.ssnmr.2024.101945","url":null,"abstract":"<div>We report solid-state 1H, 13C, and 17O NMR determination of hyperfine coupling tensors (A-tensors) in several paramagnetic Cu(II) (d9, S = 1/2) complexes: trans-Cu(DL-Ala)2·H217O, Cu([1–13C]acetate)2·H2O, Cu([2–13C]acetate)2·H2O, and Cu(acetate)2·H217O. Using these new experimental results and some A-tensor data available in the literature for trans-Cu(L-Ala)2 and K2CuCl4·2H2O, we were able to examine the accuracy of A-tensor computation from a periodic DFT method implemented in the BAND program. We evaluated A-tensors on 1H (I = 1/2), 13C (I = 1/2), 14N (I = 1), 17O (I = 5/2), 39K (I = 3/2), 35Cl (I = 3/2), and 63Cu (I = 3/2) nuclei over a range spanning more than 3 orders of magnitude. We found that the BAND code can reproduce reasonably well the experimental results for both A-tensors and nuclear quadrupole coupling tensors.</div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"132 ","pages":"Article 101945"},"PeriodicalIF":1.8,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0926204024000316/pdfft?md5=ae64e66e28bb0afa12d18d1f523805f6&pid=1-s2.0-S0926204024000316-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141538619","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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Anisotropic relaxation of nuclear spins dipolar energy of water molecules in two-dimensional nanopores - A single crystal NMR study 二维纳米孔隙中水分子核自旋偶极能的各向异性弛豫--单晶体核磁共振研究

IF 1.8 3区化学

Solid state nuclear magnetic resonance Pub Date : 2024-06-19 DOI: 10.1016/j.ssnmr.2024.101944

Alexander M. Panich , Jan Swenson

{"title":"Anisotropic relaxation of nuclear spins dipolar energy of water molecules in two-dimensional nanopores - A single crystal NMR study","authors":"Alexander M. Panich , Jan Swenson","doi":"10.1016/j.ssnmr.2024.101944","DOIUrl":"https://doi.org/10.1016/j.ssnmr.2024.101944","url":null,"abstract":"<div>Energy transfer from Zeeman to dipolar order discovered by Jeener et al. is usually observed in solids with a strong dipole-dipole interaction of nuclear spins. It is not observed in liquids, where fast molecular motion completely averages this interaction. The intermediate case, when the dipole-dipole interaction of nuclear spins is only partially averaged, has been poorly studied. We report on the first measurement of an angular-dependent proton spin relaxation of a dipolar reservoir in mobile water molecules confined in the interlayer pores of a vermiculite single crystal. In this layered crystal, the intramolecular dipole-dipole interactions of nuclear spins are only partially averaged due to the restricted anisotropic molecular motion in nanopores. We show that this allows the formation of dipolar echo. We measured the spin-lattice relaxation times of the dipolar order T1D at different angles between the normal to the crystal surface and the applied magnetic field and obtained a distinct angular dependence of T1D. The minimum relaxation rate R1D was found around the magic angle of 54.74°.</div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"132 ","pages":"Article 101944"},"PeriodicalIF":1.8,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141438408","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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Microscopic understanding of NMR signals by dynamic mean-field theory for spins 通过自旋动态平均场理论从微观角度理解核磁共振信号

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2024-05-24 DOI: 10.1016/j.ssnmr.2024.101936

Timo Gräßer , Thomas Hahn , Götz S. Uhrig

{"title":"Microscopic understanding of NMR signals by dynamic mean-field theory for spins","authors":"Timo Gräßer , Thomas Hahn , Götz S. Uhrig","doi":"10.1016/j.ssnmr.2024.101936","DOIUrl":"10.1016/j.ssnmr.2024.101936","url":null,"abstract":"<div>A recently developed dynamic mean-field theory for disordered spins (spinDMFT) is shown to capture the spin dynamics of nuclear spins very well. The key quantities are the spin autocorrelations. In order to compute the free induction decay (FID), pair correlations are needed in addition. They can be computed on spin clusters of moderate size which are coupled to the dynamic mean fields determined in a first step by spinDMFT. We dub this versatile approach non-local spinDMFT (nl-spinDMFT). It is a particular asset of nl-spinDMFT that one knows from where the contributions to the FID stem. We illustrate the strengths of nl-spinDMFT in comparison to experimental data for CaF2. Furthermore, spinDMFT provides the dynamic mean fields explaining the FID of the nuclear spins of 13C in adamantane up to some static noise. The spin Hahn echo in adamantane is free from effects of static noise and agrees excellently with the spinDMFT results without further fitting.</div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"132 ","pages":"Article 101936"},"PeriodicalIF":3.2,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0926204024000225/pdfft?md5=5c5e65aad81fd60774cb14a23ee84b0f&pid=1-s2.0-S0926204024000225-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141182730","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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Automatic fitting of multiple-field solid-state NMR spectra 自动拟合多场固态 NMR 光谱

IF 3.2 3区化学

Solid state nuclear magnetic resonance Pub Date : 2024-04-07 DOI: 10.1016/j.ssnmr.2024.101935

Frédéric A. Perras , Alexander L. Paterson

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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":"131 ","pages":"Article 101925"},"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":"130 ","pages":"Article 101923"},"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":"130 ","pages":"Article 101922"},"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}

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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":"130 ","pages":"Article 101921"},"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}

引用次数: 0