Solid state nuclear magnetic resonance最新文献

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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
{"title":"Kinetics of 1H →31P NMR cross-polarization and dynamics in a layered crystalline α-Sn(IV) phosphate","authors":"Vladimir I. Bakhmutov,&nbsp;Douglas W. Elliott,&nbsp;Hong-Cai Zhou","doi":"10.1016/j.ssnmr.2023.101898","DOIUrl":"https://doi.org/10.1016/j.ssnmr.2023.101898","url":null,"abstract":"<div><p>The proton-phosphorus (H–P) cross-polarization (CP) is effective in Sn(HPO<sub>4</sub>)<sub>2</sub>·H<sub>2</sub>O despite of the presence of paramagnetic ion impurities. Polarization constants T<sub>H-P</sub> and <sup>1</sup>H T<sub>1ρ</sub> times are measured in static Sn(HPO<sub>4</sub>)<sub>2</sub>·H<sub>2</sub>O by the kinetic variable-temperature H–P CP experiments. The temperature dependence of the <sup>1</sup>H T<sub>1ρ</sub><span> times is interpreted in terms of proton movements in the interlayer space occurring between the phosphate groups<span><span> without participation of the water molecules. The process requires an activation energy of 8.7 ± 0.7 kcal/mol. The </span>MAS effect on the </span></span><sup>1</sup>H T<sub>1ρ</sub> times is shown and discussed.</p></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"127 ","pages":"Article 101898"},"PeriodicalIF":3.2,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49857793","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
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
{"title":"Solid-state NMR of organic molecules: Characterising solid-state form","authors":"Steven P. Brown,&nbsp;Yongchao Su","doi":"10.1016/j.ssnmr.2023.101876","DOIUrl":"10.1016/j.ssnmr.2023.101876","url":null,"abstract":"","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"126 ","pages":"Article 101876"},"PeriodicalIF":3.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9975590","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
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 ,&nbsp;Fettah Aldudak ,&nbsp;Oliver Pecher ,&nbsp;Marco Braun ,&nbsp;Andreas Neuberger ,&nbsp;Holger Foysi ,&nbsp;Jörn Schmedt auf der Günne","doi":"10.1016/j.ssnmr.2023.101884","DOIUrl":"10.1016/j.ssnmr.2023.101884","url":null,"abstract":"<div><p><span>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<span> 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 </span></span>finite element<span><span> 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 </span>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.</span></p></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"126 ","pages":"Article 101884"},"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}
引用次数: 0
Remembering Shimon Vega: Special issue on solid-state and DNP NMR 纪念Shimon Vega:固态和DNP NMR特刊
IF 3.2 3区 化学
Solid state nuclear magnetic resonance Pub Date : 2023-08-01 DOI: 10.1016/j.ssnmr.2023.101885
G. Goobes, P.K. Madhu, A. Goldbourt
{"title":"Remembering Shimon Vega: Special issue on solid-state and DNP NMR","authors":"G. Goobes,&nbsp;P.K. Madhu,&nbsp;A. Goldbourt","doi":"10.1016/j.ssnmr.2023.101885","DOIUrl":"10.1016/j.ssnmr.2023.101885","url":null,"abstract":"","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"126 ","pages":"Article 101885"},"PeriodicalIF":3.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9988512","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
Spin diffusion in the Phosphorus-31 NMR relaxation in a layered crystalline α-Sn(IV) phosphate contaminated by paramagnetic impurities 顺磁杂质污染层状α-Sn(IV)磷酸盐中磷-31核磁共振弛豫的自旋扩散
IF 3.2 3区 化学
Solid state nuclear magnetic resonance Pub Date : 2023-08-01 DOI: 10.1016/j.ssnmr.2023.101875
Vladimir I. Bakhmutov , Douglas W. Elliott , Nattamai Bhuvanesh , Hong-Cai Zhou
{"title":"Spin diffusion in the Phosphorus-31 NMR relaxation in a layered crystalline α-Sn(IV) phosphate contaminated by paramagnetic impurities","authors":"Vladimir I. Bakhmutov ,&nbsp;Douglas W. Elliott ,&nbsp;Nattamai Bhuvanesh ,&nbsp;Hong-Cai Zhou","doi":"10.1016/j.ssnmr.2023.101875","DOIUrl":"10.1016/j.ssnmr.2023.101875","url":null,"abstract":"<div><p>The study of a layered crystalline Sn(IV) phosphate by solid-state NMR has demonstrated that the <sup>31</sup>P T<sub>1</sub><span><span> relaxation of phosphate groups, dependent on spinning rate is completely controlled by the limited </span>spin diffusion<span> to paramagnetic ions found by EPR. The spin-diffusion constant, D(SD), was estimated as 2.04 10</span></span><sup>−14</sup> cm<sup>2</sup>s<sup>−1</sup>. The conclusion was supported by the <sup>31</sup>P T<sub>1</sub><span> time measurements in zirconium phosphate </span><strong>1</strong>–<strong>1</strong><span>, also showing paramagnetic ions and in diamagnetic compound (NH</span><sub>4</sub>)<sub>2</sub>HPO<sub>4</sub>.</p></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"126 ","pages":"Article 101875"},"PeriodicalIF":3.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10038540","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: 1
Corrigendum to “Implanted-ion β NMR: A new probe for nanoscience” [Solid State Nucl. Magn. Reson. 68-69 (2015) 1–12] “植入离子βNMR:纳米科学的新探针”勘误表[Solid State Nucl.Magn.Reson.68-69(2015)1-12]
IF 3.2 3区 化学
Solid state nuclear magnetic resonance Pub Date : 2023-08-01 DOI: 10.1016/j.ssnmr.2023.101886
W.A. MacFarlane
{"title":"Corrigendum to “Implanted-ion β NMR: A new probe for nanoscience” [Solid State Nucl. Magn. Reson. 68-69 (2015) 1–12]","authors":"W.A. MacFarlane","doi":"10.1016/j.ssnmr.2023.101886","DOIUrl":"10.1016/j.ssnmr.2023.101886","url":null,"abstract":"","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"126 ","pages":"Article 101886"},"PeriodicalIF":3.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9983841","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
Investigating particle size effects on NMR spectra of ions diffusing in porous carbons through a mesoscopic model 通过介观模型研究离子在多孔碳中扩散的粒度对核磁共振谱的影响
IF 3.2 3区 化学
Solid state nuclear magnetic resonance Pub Date : 2023-08-01 DOI: 10.1016/j.ssnmr.2023.101883
Anagha Sasikumar , Céline Merlet
{"title":"Investigating particle size effects on NMR spectra of ions diffusing in porous carbons through a mesoscopic model","authors":"Anagha Sasikumar ,&nbsp;Céline Merlet","doi":"10.1016/j.ssnmr.2023.101883","DOIUrl":"10.1016/j.ssnmr.2023.101883","url":null,"abstract":"<div><p><span><span>Characterizing ion adsorption and diffusion in porous carbons is essential to understand the performance of such materials in a range of key technologies such as energy storage and capacitive deionisation. Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful technique to get insights in these systems thanks to its ability to distinguish between bulk and adsorbed species and to its sensitivity to dynamic phenomena. Nevertheless, a clear interpretation of the experimental results is sometimes rendered difficult by the various factors affecting </span>NMR spectra<span>. A mesoscopic model to predict NMR spectra of ions diffusing in carbon particles is adapted to include dynamic exchange between the intra-particle space and the bulk electrolyte surrounding the particle. A systematic study of the particle size effect on the NMR spectra for different distributions of magnetic environments in the porous carbons is conducted. The model demonstrates the importance of considering a range of magnetic environments, instead of a single chemical shift value corresponding to adsorbed species, and of including a range of exchange rates (between in and out of the particle), instead of a single timescale, to predict realistic NMR spectra. Depending on the </span></span>pore size distribution<span> of the carbon particle and the ratio between bulk and adsorbed species, both the NMR linewidth and peak positions can be largely influenced by the particle size.</span></p></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"126 ","pages":"Article 101883"},"PeriodicalIF":3.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9984738","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
Determination of the mutual orientation between proton CSA tensors mediated through band-selective 1H–1H recoupling under fast MAS 快速MAS下带选择性1H-1H重耦合介导的质子CSA张量相互取向的测定
IF 3.2 3区 化学
Solid state nuclear magnetic resonance Pub Date : 2023-06-01 DOI: 10.1016/j.ssnmr.2023.101874
Takeshi Kobayashi , Yusuke Nishiyama , Manoj Kumar Pandey
{"title":"Determination of the mutual orientation between proton CSA tensors mediated through band-selective 1H–1H recoupling under fast MAS","authors":"Takeshi Kobayashi ,&nbsp;Yusuke Nishiyama ,&nbsp;Manoj Kumar Pandey","doi":"10.1016/j.ssnmr.2023.101874","DOIUrl":"https://doi.org/10.1016/j.ssnmr.2023.101874","url":null,"abstract":"<div><p><span>The mutual orientation of nuclear spin interaction tensors provides critical information on the conformation and arrangement of molecules in chemicals, materials, and biological systems at an atomic level. Proton is a ubiquitous and important element in a variety of substances, and its NMR is highly sensitive due to their virtually 100% natural abundance and large gyromagnetic ratio. Nevertheless, the measurement of mutual orientation between the </span><sup>1</sup><span>H CSA tensors has remained largely untouched in the past due to strong </span><sup>1</sup>H–<sup>1</sup><span>H homonuclear interactions in a dense network of protons. In this study, we have developed a proton-detected 3D </span><sup>1</sup>H CSA/<sup>1</sup>H CSA/<sup>1</sup>H CS correlation method that utilizes three techniques to manage homonuclear interactions, namely fast magic-angle spinning, windowless <em>C</em>-symmetry-based CSA recoupling (windowless-ROCSA), and a band-selective <sup>1</sup>H–<sup>1</sup><span>H polarization transfer. The asymmetric </span><sup>1</sup>H CSA/<sup>1</sup>H CSA correlated powder patterns produced by the C-symmetry-based methods are highly sensitive to the sign and asymmetry parameter of the <sup>1</sup>H CSA, and the Euler angle <em>β</em> as compared to the symmetric pattern obtained by the existing <em>γ</em>-encoded <em>R</em>-symmetry-based CSA/CSA correlation methods and allows a larger spectral area for data fitting. These features are beneficial for determining the mutual orientation between the nuclear spin interaction tensors with improved accuracy.</p></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"125 ","pages":"Article 101874"},"PeriodicalIF":3.2,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49866177","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
Site-specific protein backbone deuterium 2Hα quadrupolar patterns by proton-detected quadruple-resonance 3D 2HαcαNH MAS NMR spectroscopy 质子检测四共振3D 2Hαcα nh MAS核磁共振谱图的位点特异性蛋白主干氘2Hα四极性图谱
IF 3.2 3区 化学
Solid state nuclear magnetic resonance Pub Date : 2023-06-01 DOI: 10.1016/j.ssnmr.2023.101861
Ümit Akbey
{"title":"Site-specific protein backbone deuterium 2Hα quadrupolar patterns by proton-detected quadruple-resonance 3D 2HαcαNH MAS NMR spectroscopy","authors":"Ümit Akbey","doi":"10.1016/j.ssnmr.2023.101861","DOIUrl":"https://doi.org/10.1016/j.ssnmr.2023.101861","url":null,"abstract":"<div><p>A novel deuterium-excited and proton-detected quadruple-resonance three-dimensional (3D) <sup>2</sup>H<sub>α</sub>c<sub>α</sub><span><span>NH MAS </span>nuclear magnetic resonance (NMR) method is presented to obtain site-specific </span><sup>2</sup>H<sub>α</sub><span> deuterium quadrupolar couplings from protein backbone, as an extension to the 2D version of the experiment reported earlier. Proton-detection results in high sensitivity compared to the heteronuclei detection methods. Utilizing four independent radiofrequency (RF) channels (quadruple-resonance), we managed to excite the </span><sup>2</sup>H<sub>α</sub>, then transfer deuterium polarization to its attached C<sub>α</sub><span>, followed by polarization transfers to the neighboring backbone nitrogen and then to the amide proton for detection. This experiment results in an easy to interpret HSQC-like 2D </span><sup>1</sup>H–<sup>15</sup><span>N fingerprint NMR spectrum, which contains site-specific deuterium quadrupolar patterns in the indirect third dimension. Provided that four-channel NMR probe technology is available, the setup of the </span><sup>2</sup>H<sub>α</sub>c<sub>α</sub>NH experiment is relatively straightforward, by using low power deuterium excitation and polarization transfer schemes we have been developing. To our knowledge, this is the first demonstration of a quadruple-resonance MAS NMR experiment to link <sup>2</sup>H<sub>α</sub> quadrupolar couplings to proton-detection, extending our previous triple-resonance demonstrations. Distortion-free excitation and polarization transfer of ∼160–170 kHz <sup>2</sup>H<sub>α</sub><span> quadrupolar coupling were presented by using a deuterium RF strength of ∼20 kHz. From these </span><sup>2</sup>H<sub>α</sub> patterns, an average backbone order parameter of S = 0.92 was determined on a deuterated SH3 sample, with an average η = 0.22. These indicate that SH3 backbone represents sizable dynamics in the microsecond timescale where the <sup>2</sup>H<sub>α</sub> lineshape is sensitive. Moreover, site-specific <sup>2</sup>H<sub>α</sub> T<sub>1</sub> relaxation times were obtained for a proof of concept. This 3D <sup>2</sup>H<sub>α</sub>c<sub>α</sub>NH NMR experiment has the potential to determine structure and dynamics of perdeuterated proteins by utilizing deuterium as a novel reporter.</p></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"125 ","pages":"Article 101861"},"PeriodicalIF":3.2,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49858070","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: 1
Cryogen-free 400 MHz (9.4 T) solid state MAS NMR system with liquid state NMR potential 无低温400 MHz (9.4 T)固态MAS核磁共振系统与液态核磁共振电位
IF 3.2 3区 化学
Solid state nuclear magnetic resonance Pub Date : 2023-06-01 DOI: 10.1016/j.ssnmr.2023.101873
Eugeny Kryukov , Alexander Karabanov , Denis Langlais , Dinu Iuga , Rupert Reckless , Jeremy Good
{"title":"Cryogen-free 400 MHz (9.4 T) solid state MAS NMR system with liquid state NMR potential","authors":"Eugeny Kryukov ,&nbsp;Alexander Karabanov ,&nbsp;Denis Langlais ,&nbsp;Dinu Iuga ,&nbsp;Rupert Reckless ,&nbsp;Jeremy Good","doi":"10.1016/j.ssnmr.2023.101873","DOIUrl":"10.1016/j.ssnmr.2023.101873","url":null,"abstract":"<div><p><span>We show that the temporal magnetic field distortion generated by the Cold Head operation can be removed and high quality Solid-State Magic Angle Spinning </span>NMR results can be obtained with a cryogen-free magnet. The compact design of the cryogen-free magnets allows for the probe to be inserted either from the bottom (as in most NMR systems) or, more conveniently, from the top. The magnetic field settling time can be made as short as an hour after a field ramp. Therefore, a single cryogen-free magnet can be used at different fixed fields. The magnetic field can be changed every day without compromising the measurement resolution.</p></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"125 ","pages":"Article 101873"},"PeriodicalIF":3.2,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9604606","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
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