1
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Schönzart J, Han R, Gennett T, Rienstra CM, Stringer JA. Magnetic Susceptibility Modeling of Magic-Angle Spinning Modules for Part Per Billion Scale Field Homogeneity. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2024; 364:107704. [PMID: 38879926 DOI: 10.1016/j.jmr.2024.107704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 05/17/2024] [Accepted: 05/18/2024] [Indexed: 06/18/2024]
Abstract
Magic-angle spinning (MAS) solid-state NMR methods are crucial in many areas of biology and materials science. Conventional probe designs have often been specified with 0.1 part per million (ppm) or 100 part per billion (ppb) magnetic field resolution, which is a limitation for many modern scientific applications. Here we describe a novel 5-mm MAS module design that significantly improves the linewidth and line shape for solid samples by an improved understanding of the magnetic susceptibility of probe materials and geometrical symmetry considerations, optimized to minimize the overall perturbation to the applied magnetic field (B0). The improved spinning module requires only first and second order shimming adjustments to achieve a sub-Hz resolution of 13C resonances of adamantane at 150 MHz Larmor frequency (14.1Tesla magnetic field). Minimal use of third and higher order shims improves experimental reproducibility upon sample changes and the exact placement within the magnet. Furthermore, the shimming procedure is faster, and the required gradients smaller, thus minimizing thermal drift of the room temperature (RT) shims. We demonstrate these results with direct polarization (Bloch decay) and cross polarization experiments on adamantane over a range of sample geometries and with multiple superconducting magnet systems. For a direct polarization experiment utilizing the entire active sample volume of a 5-mm rotor (90 µl), we achieved full width at half maximum (FWHM) of 0.76 Hz (5 ppb) and baseline resolved the 13C satellite peaks for adamantane as a consequent of the 7.31 Hz (59 ppb) width at 2% intensity. We expect these approaches to be increasingly pivotal for high-resolution solid-state NMR spectroscopy at and above 1 GHz 1H frequencies.
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Affiliation(s)
- Jasmin Schönzart
- Department of Chemistry, Colorado School of Mines, Golden, CO 80501, USA; PhoenixNMR, LLC, Loveland, CO 80503, USA.
| | - Ruixian Han
- Department of Chemistry, University of Wisconsin -Madison, Madison, WI 53706, USA
| | - Thomas Gennett
- Department of Chemistry, Colorado School of Mines, Golden, CO 80501, USA
| | - Chad M Rienstra
- Department of Chemistry, University of Wisconsin -Madison, Madison, WI 53706, USA; Department of Biochemistry, University of Wisconsin -Madison, Madison, WI 53706, USA; National Magnetic Resonance Facility at Madison, University of Wisconsin - Madison Madison, WI 53706, USA
| | - John A Stringer
- Department of Chemistry, Colorado School of Mines, Golden, CO 80501, USA; PhoenixNMR, LLC, Loveland, CO 80503, USA.
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2
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Pang Z, Tan KO. A focus on applying 63/65Cu solid-state NMR spectroscopy to characterize Cu MOFs. Chem Sci 2024; 15:6604-6607. [PMID: 38725517 PMCID: PMC11077570 DOI: 10.1039/d4sc90069c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2024] Open
Abstract
Metal-organic frameworks (MOFs) are a class of hybrid organic and inorganic porous materials that have shown prospects in applications ranging from gas storage, separation, catalysis, etc. Although they can be studied using various characterization techniques, these methods often do not provide local structural details that help explain their functionality. Zhang et al. (W. Zhang, B. E. G. Lucier, V. V. Terskikh, S. Chen and Y. Huang, Chem. Sci., 2024, https://doi.org/10.1039/D4SC00782D) have recently exploited 63/65Cu solid-state NMR spectroscopy (for the first time) and DFT calculations to elucidate the structures of Cu(i) centers in MOFs. While there are still many challenges in overcoming issues in resolution and sensitivity, this work lays the foundation for further development of solid-state NMR technology in characterizing copper in MOFs or other amorphous solids.
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Affiliation(s)
- Zhenfeng Pang
- Laboratoire des Biomolécules, LBM, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS 75005 Paris France
| | - Kong Ooi Tan
- Laboratoire des Biomolécules, LBM, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS 75005 Paris France
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3
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Zhang W, Lucier BEG, Terskikh VV, Chen S, Huang Y. Understanding Cu(i) local environments in MOFs via63/65Cu NMR spectroscopy. Chem Sci 2024; 15:6690-6706. [PMID: 38725502 PMCID: PMC11077522 DOI: 10.1039/d4sc00782d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 02/26/2024] [Indexed: 05/12/2024] Open
Abstract
The field of metal-organic frameworks (MOFs) includes a vast number of hybrid organic and inorganic porous materials with wide-ranging applications. In particular, the Cu(i) ion exhibits rich coordination chemistry in MOFs and can exist in two-, three-, and four-coordinate environments, which gives rise to many structural motifs and potential applications. Direct characterization of the structurally and chemically important Cu(i) local environments is essential for understanding the sources of specific MOF properties. For the first time, 63/65Cu solid-state NMR has been used to investigate a variety of Cu(i) sites and local coordination geometries in Cu MOFs. This approach is a sensitive probe of the local Cu environment, particularly when combined with density functional theory calculations. A wide range of structurally-dependent 63/65Cu NMR parameters have been observed, including 65Cu quadrupolar coupling constants ranging from 18.8 to 74.8 MHz. Using the data from this and prior studies, a correlation between Cu quadrupolar coupling constants, Cu coordination number, and local Cu coordination geometry has been established. Links between DFT-calculated and experimental Cu NMR parameters are also presented. Several case studies illustrate the feasibility of 63/65Cu NMR for investigating and resolving inequivalent Cu sites, monitoring MOF phase changes, interrogating the Cu oxidation number, and characterizing the product of a MOF chemical reaction involving Cu(ii) reduction to Cu(i). A convenient avenue to acquire accurate 65Cu NMR spectra and NMR parameters from Cu(i) MOFs at a widely accessible magnetic field of 9.4 T is described, with a demonstrated practical application for tracking Cu(i) coordination evolution during MOF anion exchange. This work showcases the power of 63/65Cu solid-state NMR spectroscopy and DFT calculations for molecular-level characterization of Cu(i) centers in MOFs, along with the potential of this protocol for investigating a wide variety of MOF structural changes and processes important for practical applications. This approach has broad applications for examining Cu(i) centers in other weight-dilute systems.
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Affiliation(s)
- Wanli Zhang
- Department of Chemistry, The University of Western Ontario 1151 Richmond Street London Ontario N6A 5B7 Canada
| | - Bryan E G Lucier
- Department of Chemistry, The University of Western Ontario 1151 Richmond Street London Ontario N6A 5B7 Canada
| | - Victor V Terskikh
- Metrology, National Research Council Canada Ottawa Ontario K1A 0R6 Canada
| | - Shoushun Chen
- College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 China
| | - Yining Huang
- Department of Chemistry, The University of Western Ontario 1151 Richmond Street London Ontario N6A 5B7 Canada
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4
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Bauder L, Wu G. Solid-state 35/37 Cl NMR detection of chlorine atoms directly bound to paramagnetic cobalt(II) ions in powder samples. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:145-155. [PMID: 37950603 DOI: 10.1002/mrc.5407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/12/2023] [Accepted: 10/19/2023] [Indexed: 11/12/2023]
Abstract
We report high-quality solid-state 35/37 Cl NMR spectra for chlorine atoms directly bonded to paramagnetic cobalt(II) ions (high spin S = 3/2) in powered samples of CoCl2 , CoCl2 ·2H2 O, CoCl2 ·6H2 O, and CoCl2 (terpy) (terpy = 2,2':6',2″-terpyridine). Because solid-state 35/37 Cl NMR spectra for paramagnetic cobalt(II) compounds often cover an extremely wide spectral range, they were recorded in this work in the form of variable-offset cumulative spectra. Solid-state 35/37 Cl NMR measurements were performed at three magnetic fields (11.7, 14.1, and 16.5 T) and analysis of data yielded information about 35/37 Cl quadrupole coupling and hyperfine coupling tensors in these paramagnetic cobalt(II) compounds. Experimental 35/37 Cl NMR tensors were found to be in reasonable agreement with quantum chemical calculations based on a periodic DFT method implemented in BAND.
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Affiliation(s)
- Lukas Bauder
- Department of Chemistry, Queen's University, Kingston, Ontario, Canada
| | - Gang Wu
- Department of Chemistry, Queen's University, Kingston, Ontario, Canada
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5
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Lamahewage SNS, Atterberry BA, Dorn RW, Gi E, Kimball MR, Blümel J, Vela J, Rossini AJ. Accelerated acquisition of wideline solid-state NMR spectra of spin 3/2 nuclei by frequency-stepped indirect detection experiments. Phys Chem Chem Phys 2024; 26:5081-5096. [PMID: 38259035 DOI: 10.1039/d3cp05055f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
73% of all NMR-active nuclei are quadrupolar nuclei with a nuclear spin I > 1/2. The broadening of the solid-state NMR signals by the quadrupolar interaction often leads to poor sensitivity and low resolution. In this work we present experimental and theoretical investigations of magic angle spinning (MAS) 1H{X} double-echo resonance-echo saturation-pulse double-resonance (DE-RESPDOR) and Y{X} J-resolved solid-state NMR experiments for the indirect detection of spin 3/2 quadrupolar nuclei (X = spin 3/2 nuclei, Y = spin 1/2 nuclei). In these experiments, the spectrum of the quadrupolar nucleus is reconstructed by plotting the observed dephasing of the detected spin as a function of the transmitter offset of the indirectly detected spin. Numerical simulations were used to investigate the achievable levels of dephasing and to predict the lineshapes of indirectly detected NMR spectra of the quadrupolar nucleus. We demonstrate 1H, 31P and 207Pb detection of 35Cl, 81Br, and 63Cu (I = 3/2) nuclei in trans-Cl2Pt(NH3)2 (transplatin), (CH3NH3)PbCl3 (methylammonium lead chloride, MAPbCl3), (CH3NH3)PbBr3 (methylammonium lead bromide, MAPbBr3) and CH3C(CH2PPh2)3CuI (1,1,1-tris(diphenylphosphinomethyl)ethane copper(I) iodide, triphosCuI), respectively. In all of these experiments, we were able to detect megahertz wide central transition or satellite transition powder patterns. Significant time savings and gains in sensitivity were attained in several test cases. Additionally, the indirect detection experiments provide valuable structural information because they confirm the presence of dipolar or scalar couplings between the detected nucleus and the quadrupolar nucleus of interest. Finally, numerical simulations suggest these methods are also potentially applicable to abundant spin 5/2 and spin 7/2 quadrupolar nuclei.
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Affiliation(s)
- Sujeewa N S Lamahewage
- US Department of Energy, Ames National Laboratory, Ames, Iowa, 50011, USA.
- Iowa State University, Department of Chemistry, Ames, IA, 50011, USA
| | - Benjamin A Atterberry
- US Department of Energy, Ames National Laboratory, Ames, Iowa, 50011, USA.
- Iowa State University, Department of Chemistry, Ames, IA, 50011, USA
| | - Rick W Dorn
- US Department of Energy, Ames National Laboratory, Ames, Iowa, 50011, USA.
- Iowa State University, Department of Chemistry, Ames, IA, 50011, USA
| | - Eunbyeol Gi
- US Department of Energy, Ames National Laboratory, Ames, Iowa, 50011, USA.
- Iowa State University, Department of Chemistry, Ames, IA, 50011, USA
| | - Maxwell R Kimball
- Texas A&M University, Department of Chemistry, College Station, Texas, 77842, USA.
| | - Janet Blümel
- Texas A&M University, Department of Chemistry, College Station, Texas, 77842, USA.
| | - Javier Vela
- US Department of Energy, Ames National Laboratory, Ames, Iowa, 50011, USA.
- Iowa State University, Department of Chemistry, Ames, IA, 50011, USA
| | - Aaron J Rossini
- US Department of Energy, Ames National Laboratory, Ames, Iowa, 50011, USA.
- Iowa State University, Department of Chemistry, Ames, IA, 50011, USA
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6
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Holmes ST, Schönzart J, Philips AB, Kimball JJ, Termos S, Altenhof AR, Xu Y, O'Keefe CA, Autschbach J, Schurko RW. Structure and bonding in rhodium coordination compounds: a 103Rh solid-state NMR and relativistic DFT study. Chem Sci 2024; 15:2181-2196. [PMID: 38332836 PMCID: PMC10848688 DOI: 10.1039/d3sc06026h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 12/06/2023] [Indexed: 02/10/2024] Open
Abstract
This study demonstrates the application of 103Rh solid-state NMR (SSNMR) spectroscopy to inorganic and organometallic coordination compounds, in combination with relativistic density functional theory (DFT) calculations of 103Rh chemical shift tensors and their analysis with natural bond orbital (NBO) and natural localized molecular orbital (NLMO) protocols, to develop correlations between 103Rh chemical shift tensors, molecular structure, and Rh-ligand bonding. 103Rh is one of the least receptive NMR nuclides, and consequently, there are very few reports in the literature. We introduce robust 103Rh SSNMR protocols for stationary samples, which use the broadband adiabatic inversion-cross polarization (BRAIN-CP) pulse sequence and wideband uniform-rate smooth-truncation (WURST) pulses for excitation, refocusing, and polarization transfer, and demonstrate the acquisition of 103Rh SSNMR spectra of unprecedented signal-to-noise and uniformity. The 103Rh chemical shift tensors determined from these spectra are complemented by NBO/NLMO analyses of contributions of individual orbitals to the 103Rh magnetic shielding tensors to understand their relationship to structure and bonding. Finally, we discuss the potential for these experimental and theoretical protocols for investigating a wide range of materials containing the platinum group elements.
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Affiliation(s)
- Sean T Holmes
- Department of Chemistry & Biochemistry, Florida State University Tallahassee FL 32306 USA
- National High Magnetic Field Laboratory Tallahassee FL 32310 USA
| | - Jasmin Schönzart
- Department of Chemistry & Biochemistry, Florida State University Tallahassee FL 32306 USA
- National High Magnetic Field Laboratory Tallahassee FL 32310 USA
| | - Adam B Philips
- Department of Chemistry, University at Buffalo, State University of New York Buffalo NY 14260-3000 USA
| | - James J Kimball
- Department of Chemistry & Biochemistry, Florida State University Tallahassee FL 32306 USA
- National High Magnetic Field Laboratory Tallahassee FL 32310 USA
| | - Sara Termos
- Department of Chemistry & Biochemistry, Florida State University Tallahassee FL 32306 USA
- National High Magnetic Field Laboratory Tallahassee FL 32310 USA
| | - Adam R Altenhof
- Department of Chemistry & Biochemistry, Florida State University Tallahassee FL 32306 USA
- National High Magnetic Field Laboratory Tallahassee FL 32310 USA
| | - Yijue Xu
- National High Magnetic Field Laboratory Tallahassee FL 32310 USA
| | - Christopher A O'Keefe
- Department of Chemistry & Biochemistry, University of Windsor Windsor ON N9B 3P4 Canada
| | - Jochen Autschbach
- Department of Chemistry, University at Buffalo, State University of New York Buffalo NY 14260-3000 USA
| | - Robert W Schurko
- Department of Chemistry & Biochemistry, Florida State University Tallahassee FL 32306 USA
- National High Magnetic Field Laboratory Tallahassee FL 32310 USA
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7
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Koppe J, Frerichs JE, Hansen MR. Pushing the Detection Limit of Static Wideline NMR Spectroscopy Using Ultrafast Frequency-Swept Pulses. J Phys Chem Lett 2023; 14:10748-10753. [PMID: 38010530 DOI: 10.1021/acs.jpclett.3c02758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
We report a simple design strategy for wideband uniform-rate smooth truncation (WURST) pulses that enables ultrafast frequency sweeps to maximize the sensitivity of Carr-Purcell-Meiboom-Gill (CPMG) acquisition in static wideline nuclear magnetic resonance (NMR). Three compelling examples showcase the advantage of ultrafast frequency sweeps over currently employed WURST-CPMG protocols, demonstrating the potential of investigating materials that are typically inaccessible to static wideline NMR techniques, e.g., paramagnetic solids with short homogeneous transverse relaxation times.
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Affiliation(s)
- Jonas Koppe
- Institute for Physical Chemistry, University of Münster, Corrensstrasse 28/30, DE-48149 Münster, Germany
- Centre de RMN Très Hauts Champs de Lyon (UMR5082 - CNRS, ENS Lyon, UCB Lyon 1), Université de Lyon, 5 rue de la Doua, 69100 Villeurbanne, France
| | - Joop Enno Frerichs
- Institute for Physical Chemistry, University of Münster, Corrensstrasse 28/30, DE-48149 Münster, Germany
| | - Michael Ryan Hansen
- Institute for Physical Chemistry, University of Münster, Corrensstrasse 28/30, DE-48149 Münster, Germany
- Center for Multiscale Theory and Computation (CMTC), University of Münster, Corrensstrasse 40, DE-48149 Münster, Germany
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8
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Yamada K, Kaiho T. Field-stepwise-swept solid-state 127I NMR of 1,4-diiodobenzene. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2023; 128:101905. [PMID: 38056375 DOI: 10.1016/j.ssnmr.2023.101905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 11/28/2023] [Accepted: 11/28/2023] [Indexed: 12/08/2023]
Abstract
Field-stepwise-swept solid-state 127I NMR experiments of 1,4-diiodobenzene, C6H4I2, applied to a Zeeman-perturbed NQR region, have been presented. A series of QCPMG measurements is performed at T = 90 K with resonant frequencies of 271 MHz in the range of magnetic fields from 2.5 T to zero with the interval of 12 mT. The spectral simulation, in which a numerical calculation involves the diagonalization of the combined Zeeman-quadrupolar Hamiltonian, provides quadrupole coupling constant (CQ) = 1863(5) MHz and the asymmetry parameter (ηQ) = 0.04(2). The 127I NQR spectrum is observed at T = 90 K, which is consistent in the above experimental results.
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Affiliation(s)
- Kazuhiko Yamada
- Interdisciplinary Science Unit, Multidisciplinary Sciences Cluster, Research and Education Faculty, Kochi University, Oko Campus, Nankoku, Kochi, 783-8505, Japan.
| | - Tatsuo Kaiho
- Godo Shigen Co. Ltd. , Chiba Iodine Resource Innovation Center, Chiba University, 1-33 Yayoi-Cho, Inage-Ku, Chiba, 263-8522, Japan
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9
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Kimball JJ, Altenhof AR, Jaroszewicz MJ, Schurko RW. Broadband Cross-Polarization to Half-Integer Quadrupolar Nuclei: Wideline Static NMR Spectroscopy. J Phys Chem A 2023; 127:9621-9634. [PMID: 37922436 DOI: 10.1021/acs.jpca.3c05447] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2023]
Abstract
Cross-polarization (CP) is a technique commonly used for the signal enhancement of NMR spectra; however, applications to quadrupolar nuclei have heretofore been limited due to a number of problems, including poor spin-locking efficiency, inconvenient relaxation times, and reduced CP efficiencies over broad spectral bandwidths─this is unfortunate, since they constitute 73% of NMR-active nuclei in the periodic table. The Broadband Adiabatic Inversion CP (BRAIN-CP) pulse sequence has proven useful for the signal enhancement of wideline and ultra-wideline (i.e., 250 kHz to several MHz in breadth) powder patterns arising from stationary samples; however, a comprehensive investigation of its application to half-integer quadrupolar nuclei (HIQN) is currently lacking. Herein, we present theoretical and experimental considerations for applying BRAIN-CP to acquire central-transition (CT, +1/2 ↔ -1/2) powder patterns of HIQN. Consideration is given to parameters crucial to the success of the experiment, such as the Hartmann-Hahn (HH) matching conditions and the phase modulation of the contact pulse. Modifications to the BRAIN-CP sequence such as flip-back (FB) pulses and ramped contact pulses applied to the 1H spins are used for the reduction of experimental times and increased CP bandwidth capabilities, respectively. Spectra for a series of quadrupolar nuclei with broad CT powder patterns, including 35Cl (S = 3/2), 55Mn (S = 5/2), 59Co (S = 7/2), and 93Nb (S = 9/2), are acquired via direct excitation (CPMG and WCPMG) and indirect excitation (CP/CPMG and BRAIN-CP) methods. We demonstrate that proper implementation of the sequence can enable 1H-S broadband CP over a bandwidth of 1 MHz, which to the best of our knowledge is the largest CP bandwidth reported to date. Finally, we establish the basic principles necessary for simplified optimization and execution of the BRAIN-CP pulse sequence for a wide range of HIQNs.
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Affiliation(s)
- James J Kimball
- Department of Chemistry & Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - Adam R Altenhof
- Department of Chemistry & Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - Michael J Jaroszewicz
- Department of Chemical & Biological Physics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Robert W Schurko
- Department of Chemistry & Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
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10
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Capelo R, Santos Baltieri R, de Oliveira M, Manzani D. Exploring the Influence of ZnF 2 on Zinc-Tellurite Glass: Unveiling Changes in OH Content, Structure, and Optical Properties. ACS OMEGA 2023; 8:35266-35274. [PMID: 37780030 PMCID: PMC10536076 DOI: 10.1021/acsomega.3c05010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 08/25/2023] [Indexed: 10/03/2023]
Abstract
Tellurite glasses have garnered considerable interest as optical host materials due to their advantageous properties, including low processing temperature, high resistance to corrosion and crystallization, and excellent solubility for rare earth ions. However, their applicability in the infrared (IR) region is limited by the absorption of species with distinct vibrations. The incorporation of fluorides has emerged as a promising approach to reduce hydroxyl (OH) absorption during the precursor melting process. In this study, we investigated the influence of ZnF2 on a glass matrix composed of TeO2-ZnO-Na2O, resulting in notable changes in the glass structure and optical properties, with Eu3+ serving as an environmental optical probe. The samples underwent comprehensive structural, thermal, and optical characterization. Structural analyses encompassed 19F and 125Te nuclear magnetic resonance (NMR), with the latter being complemented by mathematical simulations, and these findings were consistent with observations from Raman scattering. The main findings indicate an enhancement in thermal stability, modifications in the Te-O connectivity, and a reduction in emission intensity attributed to the effects of ligand polarizability and symmetry changes around Eu3+. Additionally, the fluorotellurite matrices exhibited a shift in the absorption edge toward higher energies, accompanied by a decrease in mid-IR absorptions, thereby expanding the transparency window. As a result, these glass matrices hold substantial potential for applications across various regions of the electromagnetic spectrum, including optical fiber drawing and the development of solid-state emitting materials.
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Affiliation(s)
- Renato
Grigolon Capelo
- São
Carlos Institute of Chemistry—IQSC, University of São Paulo—USP, São Carlos 13560-970, SP, Brazil
| | - Ricardo Santos Baltieri
- São
Carlos Institute of Chemistry—IQSC, University of São Paulo—USP, São Carlos 13560-970, SP, Brazil
| | - Marcos de Oliveira
- São
Carlos Institute of Physics—IFSC, University of São Paulo—USP, São Carlos 13560-970, SP, Brazil
| | - Danilo Manzani
- São
Carlos Institute of Chemistry—IQSC, University of São Paulo—USP, São Carlos 13560-970, SP, Brazil
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11
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Jaroszewicz MJ, Altenhof AR, Schurko RW, Frydman L. An automated multi-order phase correction routine for processing ultra-wideline NMR spectra. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 354:107528. [PMID: 37632988 DOI: 10.1016/j.jmr.2023.107528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 07/25/2023] [Accepted: 07/26/2023] [Indexed: 08/28/2023]
Abstract
Efficient acquisition of wideline solid-state nuclear magnetic resonance (NMR) spectra with patterns affected by large inhomogeneous broadening is accomplished with the use of broadband pulse sequences. These specialized pulse sequences often use frequency-swept pulses, which feature time-dependent phase and amplitude modulations that in turn deliver broad and uniform excitation across large spectral bandwidths. However, the resulting NMR spectra are often affected by complex frequency-dependent phase dispersions, owing to the interplay between the frequency-swept excitations and anisotropic resonance frequencies. Such phase distortions necessitate the use of multi-order non-linear corrections in order to obtain absorptive, distortion-free patterns with uniform phasing. Performing such corrections is often challenging due to the complex interdependence of the linear and non-linear phase contributions, and how these may affect the NMR signal. Hence, processing of these data usually involves calculating the spectra in magnitude mode wherein the phase information is discarded. Herein, we present a fully automated phasing routine that is capable of processing and phase correcting such wideline NMR spectra. Its performance is corroborated via processing of NMR data acquired using both the WURST-CPMG (Wideband, Uniform-Rate, Smooth Truncation with Carr-Purcell Meiboom-Gill acquisition) and BRAIN-CP (BRoadband Adiabatic Inversion Cross Polarization) pulse sequences for a variety of nuclei (i.e., 119Sn, 195Pt, 35Cl, 87Rb, and 14N). Based on both simulated and experimental NMR datasets, it is demonstrated that automatic phase corrections up to and including second order can be readily achieved without a priori information regarding the nature of the phase-distorted NMR datasets, and independently of the exact manner in which time-domain NMR data are collected and subsequently processed. In addition, it is shown that NMR spectra acquired at both single and multiple transmitter frequencies that are processed with this automated phasing routine have improved signal-to-noise properties than those processed with conventional magnitude calculations, along with powder patterns that better match those of ideal NMR spectra, even for datasets possessing low signal-to-noise ratios and/or affected by spectral artifacts.
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Affiliation(s)
- Michael J Jaroszewicz
- Department of Chemical and Biological Physics, Weizmann Institute, Rehovot 7610001, Israel.
| | - Adam R Altenhof
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, USA; National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA
| | - Robert W Schurko
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, USA; National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA.
| | - Lucio Frydman
- Department of Chemical and Biological Physics, Weizmann Institute, Rehovot 7610001, Israel; National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA.
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12
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Lätsch L, Kaul CJ, Yakimov AV, Müller IB, Hassan A, Perrone B, Aghazada S, Berkson ZJ, De Baerdemaeker T, Parvulescu AN, Seidel K, Teles JH, Copéret C. NMR Signatures and Electronic Structure of Ti Sites in Titanosilicalite-1 from Solid-State 47/49Ti NMR Spectroscopy. J Am Chem Soc 2023. [PMID: 37418311 DOI: 10.1021/jacs.2c09867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/09/2023]
Abstract
Although titanosilicalite-1 (TS-1) is among the most successful oxidation catalysts used in industry, its active site structure is still debated. Recent efforts have mostly focused on understanding the role of defect sites and extraframework Ti. Here, we report the 47/49Ti signature of TS-1 and molecular analogues [Ti(OTBOS)4] and [Ti(OTBOS)3(OiPr)] using novel MAS CryoProbe to enhance the sensitivity. While the dehydrated TS-1 displays chemical shifts similar to those of molecular homologues, confirming the tetrahedral environment of Ti consistent with X-ray absorption spectroscopy, it is associated with a distribution of larger quadrupolar coupling constants, indicating an asymmetric environment. Detailed computational studies on cluster models highlights the high sensitivity of the NMR signatures (chemical shift and quadrupolar coupling constant) to small local structural changes. These calculations show that, while it will be difficult to distinguish mono- vs dinuclear sites, the sensitivity of the 47/49Ti NMR signature should enable distinguishing the Ti location among specific T site positions.
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Affiliation(s)
- Lukas Lätsch
- ETH Zurich, Department of Chemistry and Applied Biosciences, Vladimir-Prelog Weg 2, CH-8093 Zurich, Switzerland
| | - Christoph J Kaul
- ETH Zurich, Department of Chemistry and Applied Biosciences, Vladimir-Prelog Weg 2, CH-8093 Zurich, Switzerland
| | - Alexander V Yakimov
- ETH Zurich, Department of Chemistry and Applied Biosciences, Vladimir-Prelog Weg 2, CH-8093 Zurich, Switzerland
| | - Imke B Müller
- BASF SE, Carl-Bosch-Straße 38, 67056 Ludwigshafen am Rhein, Germany
| | - Alia Hassan
- Bruker Switzerland, Industriestrasse 26, CH-8117 Fällanden, Switzerland
| | - Barbara Perrone
- Bruker Switzerland, Industriestrasse 26, CH-8117 Fällanden, Switzerland
| | - Sadig Aghazada
- ETH Zurich, Department of Chemistry and Applied Biosciences, Vladimir-Prelog Weg 2, CH-8093 Zurich, Switzerland
| | - Zachariah J Berkson
- ETH Zurich, Department of Chemistry and Applied Biosciences, Vladimir-Prelog Weg 2, CH-8093 Zurich, Switzerland
| | | | | | - Karsten Seidel
- BASF SE, Carl-Bosch-Straße 38, 67056 Ludwigshafen am Rhein, Germany
| | - J Henrique Teles
- BASF SE, Carl-Bosch-Straße 38, 67056 Ludwigshafen am Rhein, Germany
| | - Christophe Copéret
- ETH Zurich, Department of Chemistry and Applied Biosciences, Vladimir-Prelog Weg 2, CH-8093 Zurich, Switzerland
- Bruker Switzerland, Industriestrasse 26, CH-8117 Fällanden, Switzerland
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13
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Wolf T, Eden-Kossoy A, Frydman L. Indirectly detected satellite-transition quadrupolar NMR via progressive saturation of the proton reservoir. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2023; 125:101862. [PMID: 36989551 DOI: 10.1016/j.ssnmr.2023.101862] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 03/08/2023] [Accepted: 03/12/2023] [Indexed: 06/11/2023]
Abstract
Static satellite-transitions (ST) NMR line shapes from half-integer quadrupolar nuclei could be very informative: they can deliver insight about local motions over a wide range of timescales, and can report on small changes in the local electronic environments as reflected by variations in the quadrupolar parameters. Satellite transitions, however, are typically "invisible" for half-integer quadrupolar nuclei due to their sheer breadth, leading to low signal-to-noise ratio -especially for unreceptive low-gamma or dilute quadrupolar nuclei. Very recently we have introduced a method for enhancing the NMR sensitivity of unreceptive X nuclei in static solids dubbed PROgressive Saturation of the Proton Reservoir (PROSPR), which opens the possibility of magnifying the signals from such spins by repeatedly imprinting frequency-selective X-driven depolarizations on the much more sensitive 1H NMR signal. Here, we show that PROSPR's efficacy is high enough for enabling the detection of static ST NMR for challenging species like 35Cl, 33S and even 17O -all at natural-abundance. The ensuing ST-PROSPR NMR experiment thus opens new approaches to probe ultra-wideline (6-8 MHz wide) spectra. These highly pronounced anisotropies can in turn deliver new vistas about dynamic changes in solids, as here illustrated by tracking ST line shapes as a function of temperature during thermally-driven events.
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Affiliation(s)
- Tamar Wolf
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Anna Eden-Kossoy
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Lucio Frydman
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, 7610001, Israel.
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14
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Bernhardt M, Korzyński MD, Berkson ZJ, Pointillart F, Le Guennic B, Cador O, Copéret C. Tailored Lewis Acid Sites for High-Temperature Supported Single-Molecule Magnetism. J Am Chem Soc 2023. [PMID: 37262018 DOI: 10.1021/jacs.3c02730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Generating or even retaining slow magnetic relaxation in surface immobilized single-molecule magnets (SMMs) from promising molecular precursors remains a great challenge. Illustrative examples are organolanthanide compounds that show promising SMM properties in molecular systems, though surface immobilization generally diminishes their magnetic performance. Here, we show how tailored Lewis acidic Al(III) sites on a silica surface enable generation of a material with SMM characteristics via chemisorption of (Cpttt)2DyCl ((Cpttt)- = 1,2,4-tri(tert-butyl)-cyclopentadienide). Detailed studies of this system and its diamagnetic Y analogue indicate that the interaction of the metal chloride with surface Al sites results in a change of the coordination sphere around the metal center inducing for the dysprosium-containing material slow magnetic relaxation up to 51 K with hysteresis up to 8 K and an effective energy barrier (Ueff) of 449 cm-1, the highest reported thus far for a supported SMM.
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Affiliation(s)
- Moritz Bernhardt
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog Weg 1-5/10, 8093 Zürich, Switzerland
| | - Maciej D Korzyński
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog Weg 1-5/10, 8093 Zürich, Switzerland
| | - Zachariah J Berkson
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog Weg 1-5/10, 8093 Zürich, Switzerland
| | - Fabrice Pointillart
- Univ Rennes CNRS, ISCR (Institut des Sciences Chimiques de Rennes), UMR 6226, 35000 Rennes, France
| | - Boris Le Guennic
- Univ Rennes CNRS, ISCR (Institut des Sciences Chimiques de Rennes), UMR 6226, 35000 Rennes, France
| | - Olivier Cador
- Univ Rennes CNRS, ISCR (Institut des Sciences Chimiques de Rennes), UMR 6226, 35000 Rennes, France
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog Weg 1-5/10, 8093 Zürich, Switzerland
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15
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Hooper RW, Lin K, Veinot JGC, Michaelis VK. 3D to 0D cesium lead bromide: A 79/81Br NMR, NQR and theoretical investigation. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 352:107472. [PMID: 37186965 DOI: 10.1016/j.jmr.2023.107472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/26/2023] [Accepted: 04/30/2023] [Indexed: 05/17/2023]
Abstract
Inorganic metal halides offer unprecedented tunability through elemental variation of simple three-element compositions, but can exhibit complicated phase behaviour, degradation, and microscopic phenomena (disorder/dynamics) that play an integral role for the bulk-level chemical and physical properties of these materials. Understanding the halogen chemical environment in such materials is crucial to addressing many of the concerns regarding implementing these materials in commercial applications. In this study, a combined solid-state nuclear magnetic resonance, nuclear quadrupole resonance and quantum chemical computation approach is used to interrogate the Br chemical environment in a series of related inorganic lead bromide materials: CsPbBr3, CsPb2Br5, and Cs4PbBr6. The quadrupole coupling constants (CQ) were determined to range from 61 to 114 MHz for 81Br, with CsPbBr3 exhibiting the largest measured CQ and Cs4PbBr6 the smallest. GIPAW DFT was shown to be an excellent pre-screening tool for estimating the EFG of Br materials and can increase experimental efficiency by providing good starting estimates for acquisition. Finally, the combination of theory and experiment to inform the best methods for expanding further to the other quadrupolar halogens is discussed.
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Affiliation(s)
- Riley W Hooper
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Katherine Lin
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Jonathan G C Veinot
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Vladimir K Michaelis
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
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16
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Atterberry BA, Wimmer E, Estes DP, Rossini AJ. Acceleration of indirect detection 195Pt solid-state NMR experiments by sideband selective excitation or alternative indirect sampling schemes. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 352:107457. [PMID: 37163927 DOI: 10.1016/j.jmr.2023.107457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 03/27/2023] [Accepted: 04/12/2023] [Indexed: 05/12/2023]
Abstract
The measurement of the of chemical shift (CS) tensors via solid-state NMR (ssNMR) spectroscopy has proven to be a powerful probe of structure for organic molecules, biomolecules, and inorganic materials. However, when measuring the NMR spectra of heavy spin-1/2 isotopes the chemical shift anisotropy (CSA) is commonly on the order of thousands of parts per million, which makes acquisition of NMR spectra difficult due to the low NMR sensitivity imposed by the breadth of the signals and challenges in uniformly exciting the NMR spectrum. We have recently shown that complete 195Pt NMR spectra could be rapidly measured by using 195Pt saturation or excitation selective long pulses (SLP) with multiple rotor-cycle durations and RF fields less than 50 kHz into 1H{195Pt} or 1H-31P{195Pt} PE S-RESPDOR, TONE D-HMQC-4, J-resolved, and J-HMQC pulse sequences. The SLP only provide signal or dephasing when they are applied on resonance with a spinning sideband. The magic angle spinning 195Pt NMR spectrum is reconstructed in the sideband selective NMR experiments by acquiring 1D NMR spectra at variable 195Pt pulse offsets. In this work, we present a detailed investigation of the specific pulse conditions required for the ideal performance of sideband selective experiments. Sideband selective experiments are shown to be able to accurately reproduce MAS NMR spectra with minimal distortions of relative sideband intensities. It is also demonstrated that a 195Pt NMR spectrum indirectly detected with HMQC can be rapidly obtained by acquiring a single rotor cycle of indirect dimension evolution points. We dub this method One Rotor Cycle of Acquisition (ORCA) HMQC. Sideband selective experiments and ORCA HMQC experiments are shown to provide a one order of magnitude improvement in experiment times as compared to conventional wideline HMQC experiments.
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Affiliation(s)
- Benjamin A Atterberry
- US DOE Ames National Laboratory, Ames, IA 50011, USA; Iowa State University, Department of Chemistry, Ames, IA 50011, USA
| | - Erik Wimmer
- University of Stuttgart, Department of Chemistry, Stuttgart, Baden-Württemberg, 70569, Germany
| | - Deven P Estes
- University of Stuttgart, Department of Chemistry, Stuttgart, Baden-Württemberg, 70569, Germany
| | - Aaron J Rossini
- US DOE Ames National Laboratory, Ames, IA 50011, USA; Iowa State University, Department of Chemistry, Ames, IA 50011, USA.
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17
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Nishiyama Y, Hou G, Agarwal V, Su Y, Ramamoorthy A. Ultrafast Magic Angle Spinning Solid-State NMR Spectroscopy: Advances in Methodology and Applications. Chem Rev 2023; 123:918-988. [PMID: 36542732 PMCID: PMC10319395 DOI: 10.1021/acs.chemrev.2c00197] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Solid-state NMR spectroscopy is one of the most commonly used techniques to study the atomic-resolution structure and dynamics of various chemical, biological, material, and pharmaceutical systems spanning multiple forms, including crystalline, liquid crystalline, fibrous, and amorphous states. Despite the unique advantages of solid-state NMR spectroscopy, its poor spectral resolution and sensitivity have severely limited the scope of this technique. Fortunately, the recent developments in probe technology that mechanically rotate the sample fast (100 kHz and above) to obtain "solution-like" NMR spectra of solids with higher resolution and sensitivity have opened numerous avenues for the development of novel NMR techniques and their applications to study a plethora of solids including globular and membrane-associated proteins, self-assembled protein aggregates such as amyloid fibers, RNA, viral assemblies, polymorphic pharmaceuticals, metal-organic framework, bone materials, and inorganic materials. While the ultrafast-MAS continues to be developed, the minute sample quantity and radio frequency requirements, shorter recycle delays enabling fast data acquisition, the feasibility of employing proton detection, enhancement in proton spectral resolution and polarization transfer efficiency, and high sensitivity per unit sample are some of the remarkable benefits of the ultrafast-MAS technology as demonstrated by the reported studies in the literature. Although the very low sample volume and very high RF power could be limitations for some of the systems, the advantages have spurred solid-state NMR investigation into increasingly complex biological and material systems. As ultrafast-MAS NMR techniques are increasingly used in multidisciplinary research areas, further development of instrumentation, probes, and advanced methods are pursued in parallel to overcome the limitations and challenges for widespread applications. This review article is focused on providing timely comprehensive coverage of the major developments on instrumentation, theory, techniques, applications, limitations, and future scope of ultrafast-MAS technology.
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Affiliation(s)
- Yusuke Nishiyama
- JEOL Ltd., Akishima, Tokyo196-8558, Japan
- RIKEN-JEOL Collaboration Center, Yokohama, Kanagawa230-0045, Japan
| | - Guangjin Hou
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, 2011-Collaborative Innovation Center of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian116023, China
| | - Vipin Agarwal
- Tata Institute of Fundamental Research, Sy. No. 36/P, Gopanpally, Hyderabad500 046, India
| | - Yongchao Su
- Analytical Research and Development, Merck & Co., Inc., Rahway, New Jersey07065, United States
| | - Ayyalusamy Ramamoorthy
- Biophysics, Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, Michigan Neuroscience Institute, University of Michigan, Ann Arbor, Michigan41809-1055, United States
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18
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Costa MJ, Gonçalves AA, Rinaldi R, Bradtmüller H, Eckert H, Ferreira EB. Highly porous niobium-containing silica glasses applied to the microwave-assisted conversion of fructose into HMF. CATAL COMMUN 2022. [DOI: 10.1016/j.catcom.2022.106577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
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19
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Smith ME. Recent progress in solid-state NMR of spin-½ low-γ nuclei applied to inorganic materials. Phys Chem Chem Phys 2022; 25:26-47. [PMID: 36421944 DOI: 10.1039/d2cp03663k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Significant technological and methodological advances in solid-state NMR techniques in recent years have increased the accessibility of nuclei with small magnetic moments (hereafter termed low-γ) underpinning an increased range of applications of such nuclei. These methodological advances are briefly summarised, including improvements in hardware and pulse sequences, as well as important developments in associated computational methods (e.g. first principles calculations, spectral simulation). Here spin-½ nuclei are the focus, with this Perspective complementing a very recent review that looked at half-integer spin low-γ quadrupolar nuclei. Reference is made to some of the original reports of such spin-½ nuclei, but recent progress in the relevant methodology and applications to inorganic materials (most within the last 10 years) of these nuclei are the focus. An overview of the current state-of-the-art of studying these nuclei is thereby provided for both NMR spectroscopists and materials researchers.
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Affiliation(s)
- Mark E Smith
- Vice-Chancellor and President's Office and Department of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK. .,Department of Chemistry, Lancaster University, Bailrigg, Lancaster, LA1 4YB, UK.,Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
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20
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Venkatesh A, Gioffrè D, Atterberry BA, Rochlitz L, Carnahan SL, Wang Z, Menzildjian G, Lesage A, Copéret C, Rossini AJ. Molecular and Electronic Structure of Isolated Platinum Sites Enabled by the Expedient Measurement of 195Pt Chemical Shift Anisotropy. J Am Chem Soc 2022; 144:13511-13525. [PMID: 35861681 DOI: 10.1021/jacs.2c02300] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Techniques that can characterize the molecular structures of dilute surface species are required to facilitate the rational synthesis and improvement of Pt-based heterogeneous catalysts. 195Pt solid-state NMR spectroscopy could be an ideal tool for this task because 195Pt isotropic chemical shifts and chemical shift anisotropy (CSA) are highly sensitive probes of the local chemical environment and electronic structure. However, the characterization of Pt surface-sites is complicated by the typical low Pt loadings that are between 0.2 and 5 wt% and broadening of 195Pt solid-state NMR spectra by CSA. Here, we introduce a set of solid-state NMR methods that exploit fast MAS and indirect detection using a sensitive spy nucleus (1H or 31P) to enable the rapid acquisition of 195Pt MAS NMR spectra. We demonstrate that high-resolution wideline 195Pt MAS NMR spectra can be acquired in minutes to a few hours for a series of molecular and single-site Pt species grafted on silica with Pt loading of only 3-5 wt%. Low-power, long-duration, sideband-selective excitation, and saturation pulses are incorporated into t1-noise eliminated dipolar heteronuclear multiple quantum coherence, perfect echo resonance echo saturation pulse double resonance, or J-resolved pulse sequences. The complete 195Pt MAS NMR spectrum is then reconstructed by recording a series of 1D NMR spectra where the offset of the 195Pt pulses is varied in increments of the MAS frequency. Analysis of the 195Pt MAS NMR spectra yields the 195Pt chemical shift tensor parameters. Zeroth order approximation density functional theory calculations accurately predict 195Pt CS tensor parameters. Simple and predictive orbital models relate the CS tensor parameters to the Pt electronic structure and coordination environment. The methodology developed here paves the way for the detailed structural and electronic analysis of dilute platinum surface-sites.
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Affiliation(s)
- Amrit Venkatesh
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States.,US DOE Ames Laboratory, Ames, Iowa 50011, United States
| | - Domenico Gioffrè
- Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Benjamin A Atterberry
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States.,US DOE Ames Laboratory, Ames, Iowa 50011, United States
| | - Lukas Rochlitz
- Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Scott L Carnahan
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States.,US DOE Ames Laboratory, Ames, Iowa 50011, United States
| | - Zhuoran Wang
- Univ Lyon, ENS Lyon, Université Lyon 1, CNRS, High-Field NMR Center of Lyon, UMR 5082, F-69100 Villeurbanne, France
| | - Georges Menzildjian
- Univ Lyon, ENS Lyon, Université Lyon 1, CNRS, High-Field NMR Center of Lyon, UMR 5082, F-69100 Villeurbanne, France
| | - Anne Lesage
- Univ Lyon, ENS Lyon, Université Lyon 1, CNRS, High-Field NMR Center of Lyon, UMR 5082, F-69100 Villeurbanne, France
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Aaron J Rossini
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States.,US DOE Ames Laboratory, Ames, Iowa 50011, United States
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21
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Carvalho JP, Papawassiliou W, Pell AJ. Half-integer-spin quadrupolar nuclei in magic-angle spinning paramagnetic NMR: The case of NaMnO 2. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 340:107235. [PMID: 35644097 DOI: 10.1016/j.jmr.2022.107235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/02/2022] [Accepted: 05/08/2022] [Indexed: 06/15/2023]
Abstract
A combination of solid-state NMR methods for the extraction of 23Na shift and quadrupolar parameters in the as-synthesized, structurally complex NaMnO2 Na-ion cathode material, under magic-angle spinning (MAS) is presented. We show that the integration of the Magic-Angle Turning experiment with Rotor-Assisted Population transfer (RAPT) can be used both to identify shifts and to extract a range of magnitudes for their quadrupolar couplings. We also demonstrate the applicability of the two-dimensional one pulse (TOP) based double-sheared Satellite Transition Magic-Angle Spinning (TOP-STMAS) showing how it can yield a spectrum with separated shift and second-order quadrupolar anisotropies, which in turn can be used to analyze a quadrupolar lineshape free of anisotropic bulk magnetic susceptibility (ABMS) induced shift dispersion and determine both isotropic shift and quadrupolar products. Combining all these experiments, the shift and quadrupolar parameters for all observed Na environments were extracted and yielded excellent agreement with the density functional theory (DFT) based models that were reported in previous literature. We expect these methods to open the door for new possibilities for solid-state NMR to probe half-integer quadrupolar nuclei in paramagnetic materials and other systems exhibiting large shift dispersion.
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Affiliation(s)
- José P Carvalho
- Department of Materials and Environmental Chemistry, Stockholm University, Svante Arrhenius väg 16 C, 106 91 Stockholm, Sweden
| | - Wassilios Papawassiliou
- Department of Materials and Environmental Chemistry, Stockholm University, Svante Arrhenius väg 16 C, 106 91 Stockholm, Sweden
| | - Andrew J Pell
- Department of Materials and Environmental Chemistry, Stockholm University, Svante Arrhenius väg 16 C, 106 91 Stockholm, Sweden; Centre de RMN Très Hauts Champs de Lyon (UMR5082 - CNRS, ENS Lyon, UCB Lyon 1), Université de Lyon, 5 rue de la Doua, 69100 Villeurbanne, France.
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22
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Daniels CL, Gi E, Atterberry BA, Blome-Fernández R, Rossini AJ, Vela J. Phosphine Ligand Binding and Catalytic Activity of Group 10-14 Heterobimetallic Complexes. Inorg Chem 2022; 61:6888-6897. [PMID: 35481778 DOI: 10.1021/acs.inorgchem.2c00229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Heterobimetallic complexes have attracted much interest due to their broad range of structures and reactivities as well as unique catalytic abilities. Additionally, these complexes can be utilized as single-source precursors for the synthesis of binary intermetallic compounds. An example is the family of bis(pyridine-2-thiolato)dichloro-germanium and tin complexes of group 10 metals (Pd and Pt). The reactivity of these heterobimetallic complexes is highly tunable through substitution of the group 14 element and the neutral ligand bound to the transition metal. Here, we study the binding energies of three different phosphorous-based ligands, PR3 (R = Bu, Ph, and OPh) by density functional theory and restricted Hartree-Fock methods. The PR3 ligand-binding energies follow the trend of PBu3 > PPh3 > P(OPh)3, in agreement with their sigma-bonding ability. These results are confirmed by ligand exchange experiments monitored with 31P NMR spectroscopy, in which a weaker binding PR3 ligand is replaced with a stronger one. Furthermore, we demonstrate that the heterobimetallic complexes are active catalysts in the Negishi coupling reaction, where stronger binding PR3 ligands inhibit access to an active site at the metal center. Similar strategies could be applied to other complexes to better understand their ligand-binding energetics and predict their reactivity as both precursors and catalysts.
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Affiliation(s)
- Carena L Daniels
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - Eunbyeol Gi
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States.,US DOE Ames Laboratory, Ames, Iowa 50011, United States
| | - Benjamin A Atterberry
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States.,US DOE Ames Laboratory, Ames, Iowa 50011, United States
| | | | - Aaron J Rossini
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States.,US DOE Ames Laboratory, Ames, Iowa 50011, United States
| | - Javier Vela
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States.,US DOE Ames Laboratory, Ames, Iowa 50011, United States
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23
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Altenhof AR, Gan Z, Schurko RW. Reducing the effects of weak homonuclear dipolar coupling with CPMG pulse sequences for static and spinning solids. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 337:107174. [PMID: 35279507 DOI: 10.1016/j.jmr.2022.107174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 02/18/2022] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
The Carr-Purcell/Meiboom-Gill (CPMG) pulse sequence, initially introduced for measuring transverse relaxation time constants (T2), can provide significant signal enhancements for solid-state NMR (SSNMR) spectra. The proper implementation of CPMG for acquiring spectra influenced by chemical shift anisotropies (CSAs), first and/or second order quadrupolar interactions, or paramagnetic broadening has been well documented to date, as have the effects of heteronuclear dipolar coupling on CPMG echo trains and T2 lifetimes. Homonuclear dipolar coupling can also impact T2 lifetimes and CPMG echo trains; these effects have been thoroughly investigated for spectra of homonuclear dipolar coupled spin-1/2 nuclei typically acquired under static conditions that are predominantly influenced by dipolar broadening (e.g., 1H, 19F, etc.). In particular, it has been shown that short refocusing pulses with small flip angles can extend the effective T2 (T2eff, the observed T2 constant as impacted by experimental conditions) measured by CPMG sequences for strong homonuclear dipolar coupled spin-1/2 pairs under static conditions. To date, these effects have not been explored for (i) spin-1/2 nuclei that have significant CSAs and simultaneously feature weak homonuclear dipolar couplings, (ii) for quadrupolar nuclei that are also weakly homonuclear dipolar coupled, and (iii) for either of these cases under magic-angle spinning (MAS) conditions. Herein, we demonstrate that short refocusing pulses that cause small flip angles can reduce the attenuation of signal in CPMG echo trains resulting from dipolar dephasing caused by the weak homonuclear dipolar couplings. For both spin-1/2 and quadrupolar nuclei, this can lead to significant extensions in T2eff and signal enhancements of up to three times compared to conventional CPMG in favourable cases. These phenomena can occur under both static and magic-angle spinning (MAS) conditions, in the latter of which homonuclear couplings are reintroduced by rotational resonance (R2) recoupling. Experimental examples of 13C (I = 1/2), 2H (I = 1), 87Rb (I = 3/2), 23Na (I = 3/2), and 35Cl (I = 3/2) NMR under static and MAS conditions, as well as simulations of these phenomena, are shown and discussed.
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Affiliation(s)
- Adam R Altenhof
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, USA; National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA
| | - Zhehong Gan
- National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA
| | - Robert W Schurko
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, USA; National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA.
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24
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Bayzou R, Trébosc J, Hung I, Gan Z, Lafon O, Amoureux JP. Indirect NMR detection via proton of nuclei subject to large anisotropic interactions, such as 14N, 195Pt, and 35Cl, using the T-HMQC sequence. J Chem Phys 2022; 156:064202. [DOI: 10.1063/5.0082700] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Racha Bayzou
- Univ. Lille, CNRS, Centrale Lille, Univ. Artois, UMR 8181–UCCS–Unité de Catalyse et Chimie du Solide, 59000 Lille, France
| | - Julien Trébosc
- Univ. Lille, CNRS, INRAE, Centrale Lille, Univ. Artois, FR 2638–IMEC–Fédération Chevreul, 59000 Lille, France
| | - Ivan Hung
- National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, USA
| | - Zhehong Gan
- National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, USA
| | - Olivier Lafon
- Univ. Lille, CNRS, Centrale Lille, Univ. Artois, UMR 8181–UCCS–Unité de Catalyse et Chimie du Solide, 59000 Lille, France
| | - Jean-Paul Amoureux
- Univ. Lille, CNRS, Centrale Lille, Univ. Artois, UMR 8181–UCCS–Unité de Catalyse et Chimie du Solide, 59000 Lille, France
- Riken NMR Science and Development Division, Yokohama-shi 230-0045, Kanagawa, Japan
- Bruker Biospin, 34 rue de l’industrie, 67166 Wissembourg, France
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25
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Altenhof AR, Jaroszewicz MJ, Frydman L, Schurko R. 3D Relaxation-Assisted Separation of Wideline Solid-State NMR Patterns for Achieving Site Resolution. Phys Chem Chem Phys 2022; 24:22792-22805. [DOI: 10.1039/d2cp00910b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
There are currently no methods for the acquisition of ultra-wideline (UW) solid-state NMR spectra under static conditions that enable reliable separation and resolution of overlapping powder patterns arising from magnetically...
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26
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Jaroszewicz M, Altenhof AR, Schurko RW, Frydman L. Sensitivity Enhancement by Progressive Saturation of the Proton Reservoir: A Solid-State NMR Analogue of Chemical Exchange Saturation Transfer. J Am Chem Soc 2021; 143:19778-19784. [PMID: 34793152 PMCID: PMC8640991 DOI: 10.1021/jacs.1c08277] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Indexed: 01/10/2023]
Abstract
Chemical exchange saturation transfer (CEST) enhances solution-state NMR signals of labile and otherwise invisible chemical sites, by indirectly detecting their signatures as a highly magnified saturation of an abundant resonance─for instance, the 1H resonance of water. Stimulated by this sensitivity magnification, this study presents PROgressive Saturation of the Proton Reservoir (PROSPR), a method for enhancing the NMR sensitivity of dilute heteronuclei in static solids. PROSPR aims at using these heteronuclei to progressively deplete the abundant 1H polarization found in most organic and several inorganic solids, and implements this 1H signal depletion in a manner that reflects the spectral intensities of the heteronuclei as a function of their chemical shifts or quadrupolar offsets. To achieve this, PROSPR uses a looped cross-polarization scheme that repeatedly depletes 1H-1H local dipolar order and then relays this saturation throughout the full 1H reservoir via spin-diffusion processes that act as analogues of chemical exchanges in the CEST experiment. Repeating this cross-polarization/spin-diffusion procedure multiple times results in an effective magnification of each heteronucleus's response that, when repeated in a frequency-stepped fashion, indirectly maps their NMR spectrum as sizable attenuations of the abundant 1H NMR signal. Experimental PROSPR examples demonstrate that, in this fashion, faithful wideline NMR spectra can be obtained. These 1H-detected heteronuclear NMR spectra can have their sensitivity enhanced by orders of magnitude in comparison to optimized direct-detect experiments targeting unreceptive nuclei at low natural abundance, using modest hardware requirements and conventional NMR equipment at room temperature.
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Affiliation(s)
- Michael
J. Jaroszewicz
- Department
of Chemical and Biological Physics, Weizmann
Institute of Science, Rehovot 7610001, Israel
| | - Adam R. Altenhof
- Department
of Chemistry and Biochemistry, Florida State
University, Tallahassee, Florida 32306, United States
- National
High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, United States
| | - Robert W. Schurko
- Department
of Chemistry and Biochemistry, Florida State
University, Tallahassee, Florida 32306, United States
- National
High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, United States
| | - Lucio Frydman
- Department
of Chemical and Biological Physics, Weizmann
Institute of Science, Rehovot 7610001, Israel
- National
High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, United States
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27
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Holmes ST, Hook JM, Schurko RW. Nutraceuticals in Bulk and Dosage Forms: Analysis by 35Cl and 14N Solid-State NMR and DFT Calculations. Mol Pharm 2021; 19:440-455. [PMID: 34792373 DOI: 10.1021/acs.molpharmaceut.1c00708] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This study uses 35Cl and 14N solid-state NMR (SSNMR) spectroscopy and dispersion-corrected plane-wave density functional theory (DFT) calculations for the structural characterization of chloride salts of nutraceuticals in their bulk and dosage forms. For eight nutraceuticals, we measure the 35Cl EFG tensor parameters of the chloride ions and use plane-wave DFT calculations to elucidate relationships between NMR parameters and molecular-level structure, which provide rapid NMR crystallographic assessments of structural features. We employ both 35Cl direct excitation and 1H→35Cl cross-polarization methods to characterize a dosage form containing α-d-glucosamine HCl, observe possible impurity and/or adulterant phases, and quantify the weight percent of the active ingredient. To complement this, we also investigate 14N SSNMR spectroscopy and DFT calculations to characterize nitrogen atoms in the nutraceuticals. This includes a discussion of targeted acquisition experimental protocols (i.e., acquiring a select region of the overall pattern that features key discontinuities) that allow ultrawideline spectra to be acquired rapidly, even for unreceptive samples (i.e., those with long values of T1(14N), short values of T2eff(14N), or very broad patterns). It is hoped that these experimental and computational protocols will be useful for the characterization of various solid forms of nutraceuticals (i.e., salts, polymorphs, hydrates, solvates, cocrystals, amorphous solid dispersions, etc.), help detect impurity and counterfeit solid phases in dosage forms, and serve as a foundation for future NMR crystallographic studies of nutraceutical solid forms, including studies using ab initio crystal structure prediction algorithms.
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Affiliation(s)
- Sean T Holmes
- Department of Chemistry & Biochemistry, Florida State University, Tallahassee, Florida 32306, United States.,National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - James M Hook
- NMR Facility, Mark Wainwright Analytical Centre, The University of New South Wales, Sydney, New South Wales 2052, Australia.,School of Chemistry, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Robert W Schurko
- Department of Chemistry & Biochemistry, Florida State University, Tallahassee, Florida 32306, United States.,National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
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28
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Reconstructing Reliable Powder Patterns from Spikelets (Q)CPMG NMR Spectra: Simplification of UWNMR Crystallography Analysis. Molecules 2021; 26:molecules26196051. [PMID: 34641595 PMCID: PMC8513071 DOI: 10.3390/molecules26196051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 09/29/2021] [Accepted: 09/30/2021] [Indexed: 11/16/2022] Open
Abstract
Spikelets NMR spectra are very popular as they enable the shortening of experimental time and give the possibility to obtain required NMR parameters for nuclei with ultrawide NMR patterns. Unfortunately, these resulted ssNMR spectra cannot be fitted directly in common software. For this reason, we developed UWNMRSpectralShape (USS) software which transforms spikelets NMR patterns into single continuous lines. Subsequently, these reconstructed spectral envelopes of the (Q)CPMG spikelets patterns can be loaded into common NMR software and automatically fitted, independently of experimental settings. This allows the quadrupole and chemical shift parameters to be accurately determined. Moreover, it makes fitting of spikelets NMR spectra exact, fast and straightforward.
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29
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Wübker A, Koppe J, Bradtmüller H, Keweloh L, Pleschka D, Uhl W, Hansen MR, Eckert H. Solid-State Nuclear Magnetic Resonance Techniques for the Structural Characterization of Geminal Alane-Phosphane Frustrated Lewis Pairs and Secondary Adducts. Chemistry 2021; 27:13249-13257. [PMID: 34270155 PMCID: PMC8518393 DOI: 10.1002/chem.202102113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Indexed: 11/17/2022]
Abstract
The first comprehensive solid-state nuclear magnetic resonance (NMR) characterization of geminal alane-phosphane frustrated Lewis pairs (Al/P FLPs) is reported. Their relevant NMR parameters (isotropic chemical shifts, direct and indirect 27 Al-31 P spin-spin coupling constants, and 27 Al nuclear electric quadrupole coupling tensor components) have been determined by numerical analysis of the experimental NMR line shapes and compared with values computed from the known crystal structures by using density functional theory (DFT) methods. Our work demonstrates that the 31 P NMR chemical shifts for the studied Al/P FLPs are very sensitive to slight structural inequivalences. The 27 Al NMR central transition signals are spread out over a broad frequency range (>200 kHz), owing to the presence of strong nuclear electric quadrupolar interactions that can be well-reproduced by the static 27 Al wideband uniform rate smooth truncation (WURST) Carr-Purcell-Meiboom-Gill (WCPMG) NMR experiment. 27 Al chemical shifts and quadrupole tensor components offer a facile and clear distinction between three- and four-coordinate aluminum environments. For measuring internuclear Al⋅⋅⋅P distances a new resonance-echo saturation-pulse double-resonance (RESPDOR) experiment was developed by using efficient saturation via frequency-swept WURST pulses. The successful implementation of this widely applicable technique indicates that internuclear Al⋅⋅⋅P distances in these compounds can be measured within a precision of ±0.1 Å.
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Affiliation(s)
- Anna‐Lena Wübker
- Institut für Physikalische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Jonas Koppe
- Institut für Physikalische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Henrik Bradtmüller
- Institut für Physikalische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
- Department of Materials EngineeringVitreous Materials LaboratoryFederal University of São CarlosCP 67613565-905São CarlosSPBrazil
| | - Lukas Keweloh
- Institut für Anorganische und Analytische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Damian Pleschka
- Institut für Anorganische und Analytische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Werner Uhl
- Institut für Anorganische und Analytische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Michael Ryan Hansen
- Institut für Physikalische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Hellmut Eckert
- Institut für Physikalische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
- Instituto de Física de São CarlosUniversidade de São PauloSão CarlosSP13566-590Brazil
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30
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Laurencin D, Li Y, Duer MJ, Iuga D, Gervais C, Bonhomme C. A 43 Ca nuclear magnetic resonance perspective on octacalcium phosphate and its hybrid derivatives. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:1048-1061. [PMID: 33729624 DOI: 10.1002/mrc.5149] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 03/01/2021] [Accepted: 03/08/2021] [Indexed: 06/12/2023]
Abstract
43 Ca nuclear magnetic resonance (NMR) spectroscopy has been extensively applied to the detailed study of octacalcium phosphate (OCP), Ca8 (HPO4 )2 (PO4 )4 .5H2 O, and hybrid derivatives involving intercalated metabolic acids (viz., citrate, succinate, formate, and adipate). Such phases are of importance in the development of a better understanding of bone structure. High-resolution 43 Ca magic angle spinning (MAS) experiments, including double-rotation (DOR) 43 Ca NMR, as well as 43 Ca{1 H} rotational echo DOR (REDOR) and 31 P{43 Ca} REAPDOR NMR spectra, were recorded on a 43 Ca-labeled OCP phase at very high magnetic field (20 T), and complemented by ab initio calculations of NMR parameters using the Gauge-Including Projector Augmented Wave-density functional theory (GIPAW-DFT) method. This enabled a partial assignment of the eight inequivalent Ca2+ sites of OCP. Natural-abundance 43 Ca MAS NMR spectra were then recorded for the hybrid organic-inorganic derivatives, revealing changes in the 43 Ca lineshape. In the case of the citrate derivative, these could be interpreted on the basis of computational models of the structure. Overall, this study highlights the advantages of combining high-resolution 43 Ca NMR experiments and computational modeling for studying complex hybrid biomaterials.
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Affiliation(s)
| | - Yang Li
- Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Melinda J Duer
- Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Dinu Iuga
- Department of Physics, University of Warwick, Coventry, UK
| | - Christel Gervais
- LCMCP-Chemistry of Condensed Matter Laboratory of Paris, Sorbonne University, Paris, France
| | - Christian Bonhomme
- LCMCP-Chemistry of Condensed Matter Laboratory of Paris, Sorbonne University, Paris, France
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31
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Altenhof AR, Wi S, Schurko RW. Broadband adiabatic inversion cross-polarization to integer-spin nuclei with application to deuterium NMR. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:1009-1023. [PMID: 33634894 DOI: 10.1002/mrc.5145] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 02/15/2021] [Accepted: 02/22/2021] [Indexed: 06/12/2023]
Abstract
Solid-state NMR (SSNMR) spectroscopy of integer-spin quadrupolar nuclei is important for the molecular-level characterization of a variety of materials and biological solids; of the integer spins, 2 H (S = 1) is by far the most widely studied, due to its usefulness in probing dynamical motions. SSNMR spectra of integer-spin nuclei often feature very broad powder patterns that arise largely from the effects of the first-order quadrupolar interaction; as such, the acquisition of high-quality spectra continues to remain a challenge. The broadband adiabatic inversion cross-polarization (BRAIN-CP) pulse sequence, which is capable of cross-polarization (CP) enhancement over large bandwidths, has found success for the acquisition of SSNMR spectra of integer-spin nuclei, including 14 N (S = 1), especially when coupled with Carr-Purcell/Meiboom-Gill pulse sequences featuring frequency-swept WURST pulses (WURST-CPMG) for T2 -based signal enhancement. However, to date, there has not been a systematic investigation of the spin dynamics underlying BRAIN-CP, nor any concrete theoretical models to aid in its parameterization for applications to integer-spin nuclei. In addition, the BRAIN-CP/WURST-CPMG scheme has not been demonstrated for generalized application to wideline or ultra-wideline (UW) 2 H SSNMR. Herein, we provide a theoretical description of the BRAIN-CP pulse sequence for spin-1/2 → spin-1 CP under static conditions, featuring a set of analytical equations describing Hartmann-Hahn matching conditions and numerical simulations that elucidate a CP mechanism involving polarization transfer, coherence exchange, and adiabatic inversion. Several experimental examples are presented for comparison with theoretical models and previously developed integer-spin CP methods, demonstrating rapid acquisition of 2 H NMR spectra from efficient broadband CP.
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Affiliation(s)
- Adam R Altenhof
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida, USA
- National High Magnetic Field Laboratory, Tallahassee, Florida, USA
| | - Sungsool Wi
- National High Magnetic Field Laboratory, Tallahassee, Florida, USA
| | - Robert W Schurko
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida, USA
- National High Magnetic Field Laboratory, Tallahassee, Florida, USA
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32
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Smith ME. Recent progress in solid-state nuclear magnetic resonance of half-integer spin low-γ quadrupolar nuclei applied to inorganic materials. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:864-907. [PMID: 33207003 DOI: 10.1002/mrc.5116] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/12/2020] [Accepted: 11/13/2020] [Indexed: 06/11/2023]
Abstract
An overview is presented of recent progress in the solid-state nuclear magnetic resonance (NMR) observation of low-γ nuclei, with a focus on applications to inorganic materials. The technological and methodological advances in the last 20 years, which have underpinned the increased accessibility of low-γ nuclei for study by solid-state NMR techniques, are summarised, including improvements in hardware, pulse sequences and associated computational methods (e.g., first principles calculations and spectral simulation). Some of the key initial observations from inorganic materials of these nuclei are highlighted along with some recent (most within the last 10 years) illustrations of their application to such materials. A summary of other recent reviews of the study of low-γ nuclei by solid-state NMR is provided so that a comprehensive understanding of what has been achieved to date is available.
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Affiliation(s)
- Mark E Smith
- Vice-Chancellor and President's Office and Department of Chemistry, University of Southampton, Southampton, UK
- Department of Chemistry, Lancaster University, Bailrigg, Lancaster, UK
- Department of Physics, University of Warwick, Coventry, UK
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33
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Griffith KJ, Ding F, Flynn S. Solid-state nuclear magnetic resonance of spin-9/2 nuclei 115 In and 209 Bi in functional inorganic complex oxides. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:1077-1088. [PMID: 34081358 DOI: 10.1002/mrc.5183] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 05/24/2021] [Accepted: 05/29/2021] [Indexed: 05/02/2023]
Abstract
Indium and bismuth are technologically important elements, in particular as oxides for optoelectronic applications. 115 In and 209 Bi are both I = 9/2 nuclei with high natural abundances and moderately high frequencies but large nuclear electric quadrupole moments. Leveraging the quadrupolar interaction as a measure of local symmetry and polyhedral distortions for these nuclei could provide powerful insights on a range of applied materials. However, the absence of reported nuclear magnetic resonance (NMR) parameters on these nuclei, particularly in oxides, hinders their use by the broader materials community. In this contribution, solid-state 115 In and 209 Bi NMR of three recently discovered quaternary bismuth or indium oxides are reported, supported by density functional theory calculations, numerical simulations, diffraction and additional multinuclear (27 Al, 69,71 Ga, and 121 Sb) solid-state NMR measurements. The compounds LiIn2 SbO6 , BiAlTeO6 , and BiGaTeO6 are measured without special equipment at 9.4 T, demonstrating that wideline techniques such as the QCPMG pulse sequence and frequency-stepped acquisition can enable straightforward extraction of quadrupolar tensor information in I = 9/2 115 In and 209 Bi even in sites with large quadrupolar coupling constants. Relationships are described between the NMR observables and local site symmetry. These are amongst the first reports of the NMR parameters of 115 In, 121 Sb, and 209 Bi in oxides.
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Affiliation(s)
- Kent J Griffith
- Department of Chemistry, Northwestern University, Evanston, Illinois, USA
| | - Fenghua Ding
- Department of Chemistry, Northwestern University, Evanston, Illinois, USA
| | - Steven Flynn
- Department of Chemistry, Northwestern University, Evanston, Illinois, USA
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34
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Fernandes A, Moran RF, McKay D, Griffiths BL, Herlihy A, Whittle KR, Dawson DM, Ashbrook SE. Exploring cation disorder in mixed-metal pyrochlore ceramics using 17 O NMR spectroscopy and first-principles calculations. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:961-974. [PMID: 33565625 DOI: 10.1002/mrc.5140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 02/05/2021] [Indexed: 06/12/2023]
Abstract
Characterising the local structures (e.g., the cation distribution) of mixed-metal ceramics by NMR spectroscopy is often challenging owing to the unfavourable properties (low γ, large quadrupole moment and/or low abundance) of many metal nuclei. 17 O is an attractive option owing to the prevalence of oxygen within ceramics. The moderate γ and small quadrupole moment of 17 O mean that the greatest barrier to accessing the information available from this nucleus is isotopic enrichment. We explore the challenges of ensuring uniform isotopic enrichment with 17 O2 (g) for the pyrochlore solid solutions, Y2 Snx Ti2-x O7 , La2 Snx Zr2-x O7 and La2 Snx Hf2-x O7 , demonstrating that high enrichment temperatures (900 °C for 12 hr) are required. In addition, for sites with very high symmetry (such as the tetrahedral OY4 and OLa4 sites with CQ ≈ 0 present here), we demonstrate that quantitative 17 O NMR spectra require correction for the differing contributions from the centreband of the satellite transitions, which can be as high as a factor of ~3.89. It is common to use first-principles calculations to aid in interpreting NMR spectra of disordered solids. Here, we use an ensemble modelling approach to ensure that all possible cation arrangements are modelled in the minimum possible number of calculations. By combining uniform isotopic enrichment, quantitative NMR spectroscopy and a comprehensive computational approach, we are able to show that the cation distribution in Y2 Snx Ti2-x O7 is essentially random, whereas in La2 Snx Zr2-x O7 and La2 Snx Hf2-x O7 , OLa2SnZr and OLa2SnHf sites are slightly energetically disfavoured, leading to a weak preference for clustering of like cations.
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Affiliation(s)
- Arantxa Fernandes
- School of Chemistry, EaStCHEM and Centre of Magnetic Resonance, University of St Andrews, St Andrews, UK
| | - Robert F Moran
- School of Chemistry, EaStCHEM and Centre of Magnetic Resonance, University of St Andrews, St Andrews, UK
| | - David McKay
- School of Chemistry, EaStCHEM and Centre of Magnetic Resonance, University of St Andrews, St Andrews, UK
| | - Ben L Griffiths
- School of Chemistry, EaStCHEM and Centre of Magnetic Resonance, University of St Andrews, St Andrews, UK
| | - Anna Herlihy
- School of Chemistry, EaStCHEM and Centre of Magnetic Resonance, University of St Andrews, St Andrews, UK
| | - Karl R Whittle
- School of Engineering, University of Liverpool, Liverpool, UK
| | - Daniel M Dawson
- School of Chemistry, EaStCHEM and Centre of Magnetic Resonance, University of St Andrews, St Andrews, UK
| | - Sharon E Ashbrook
- School of Chemistry, EaStCHEM and Centre of Magnetic Resonance, University of St Andrews, St Andrews, UK
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35
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Hung I, Altenhof AR, Schurko RW, Bryce DL, Han OH, Gan Z. Field-stepped ultra-wideline NMR at up to 36 T: On the inequivalence between field and frequency stepping. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:951-960. [PMID: 33373086 PMCID: PMC8239055 DOI: 10.1002/mrc.5128] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/16/2020] [Accepted: 12/23/2020] [Indexed: 06/12/2023]
Abstract
Field-stepped NMR spectroscopy at up to 36 T using the series-connected hybrid (SCH) magnet at the U.S. National High Magnetic Field Laboratory is demonstrated for acquiring ultra-wideline powder spectra of nuclei with very large quadrupolar interactions. Historically, NMR evolved from the continuous-wave (cw) field-swept method in the early days to the pulsed Fourier-transform method in the modern era. Spectra acquired using field sweeping are generally considered to be equivalent to those acquired using the pulsed method. Here, it is shown that field-stepped wideline spectra of half-integer spin quadrupolar nuclei acquired using WURST/CPMG methods can be significantly different from those acquired with the frequency-stepped method commonly used with superconducting magnets. The inequivalence arises from magnetic field-dependent NMR interactions such as the anisotropic chemical shift and second-order quadrupolar interactions; the latter is often the main interaction leading to ultra-wideline powder patterns of half-integer spin quadrupolar nuclei. This inequivalence needs be taken into account to accurately and correctly determine the quadrupolar coupling and chemical shift parameters. A simulation protocol is developed for spectral fitting to facilitate analysis of field-stepped ultra-wideline NMR spectra acquired using powered magnets. A MATLAB program which implements this protocol is available on request.
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Affiliation(s)
- Ivan Hung
- National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
| | - Adam R Altenhof
- National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, 32306, USA
| | - Robert W Schurko
- National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, 32306, USA
| | - David L Bryce
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | - Oc Hee Han
- Western Seoul Center, Korea Basic Science Institute, Seoul, 03759, South Korea
| | - Zhehong Gan
- National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
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36
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NMR spectroscopy probes microstructure, dynamics and doping of metal halide perovskites. Nat Rev Chem 2021; 5:624-645. [PMID: 37118421 DOI: 10.1038/s41570-021-00309-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2021] [Indexed: 12/23/2022]
Abstract
Solid-state magic-angle spinning NMR spectroscopy is a powerful technique to probe atomic-level microstructure and structural dynamics in metal halide perovskites. It can be used to measure dopant incorporation, phase segregation, halide mixing, decomposition pathways, passivation mechanisms, short-range and long-range dynamics, and other local properties. This Review describes practical aspects of recording solid-state NMR data on halide perovskites and how these afford unique insights into new compositions, dopants and passivation agents. We discuss the applicability, feasibility and limitations of 1H, 13C, 15N, 14N, 133Cs, 87Rb, 39K, 207Pb, 119Sn, 113Cd, 209Bi, 115In, 19F and 2H NMR in typical experimental scenarios. We highlight the pivotal complementary role of solid-state mechanosynthesis, which enables highly sensitive NMR studies by providing large quantities of high-purity materials of arbitrary complexity and of chemical shifts calculated using density functional theory. We examine the broader impact of solid-state NMR on materials research and how its evolution over seven decades has benefitted structural studies of contemporary materials such as halide perovskites. Finally, we summarize some of the open questions in perovskite optoelectronics that could be addressed using solid-state NMR. We, thereby, hope to stimulate wider use of this technique in materials and optoelectronics research.
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37
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Koppe J, Bußkamp M, Hansen MR. Frequency-Swept Ultra-Wideline Magic-Angle Spinning NMR Spectroscopy. J Phys Chem A 2021; 125:5643-5649. [PMID: 34138561 DOI: 10.1021/acs.jpca.1c02958] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recent years have witnessed the development of solid-state NMR techniques that allow the direct investigation of extremely wide inhomogeneously broadened resonance lines. To date, this typically involves the application of frequency sweeps as offered by wideband uniform rate smooth truncation (WURST) pulses. While the effects of such advanced irradiation schemes on static samples are well understood, the interference between the varying carrier frequency and the time-dependent evolution of the spin system under magic-angle spinning (MAS) conditions is more complex. Herein, we introduce the well-known WURST-Carr-Purcell-Meiboom-Gill (WCPMG) pulse sequence for spinning samples. Using numerical spin-density matrix analysis, an ideal design based on fast frequency sweeps and high truncation of the incorporated WURST pulses is presented that enables uniform excitation/refocusing under MAS conditions with low-to-moderate radio-frequency power requirements. This permits the acquisition of ultra-wideline MAS NMR lines exceeding 500 kHz with chemical shift resolution in a single transmitter step.
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Affiliation(s)
- Jonas Koppe
- Institute for Physical Chemistry, Westfälische Wilhelms-Universität, Corrensstr. 28/30, DE-48149 Münster, Germany
| | - Max Bußkamp
- Institute for Physical Chemistry, Westfälische Wilhelms-Universität, Corrensstr. 28/30, DE-48149 Münster, Germany
| | - Michael Ryan Hansen
- Center for Multiscale Theory and Computation (CMTC), Westfälische Wilhelms-Universität, Corrensstrasse 40, DE-48149 Münster, Germany
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38
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Venkatesh A, Perras FA, Rossini AJ. Proton-detected solid-state NMR spectroscopy of spin-1/2 nuclei with large chemical shift anisotropy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 327:106983. [PMID: 33964731 DOI: 10.1016/j.jmr.2021.106983] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/05/2021] [Accepted: 04/10/2021] [Indexed: 06/12/2023]
Abstract
Constant-time (CT) dipolar heteronuclear multiple quantum coherence (D-HMQC) has previously been demonstrated as a method for proton detection of high-resolution wideline NMR spectra of spin-1/2 nuclei with large chemical shift anisotropy (CSA). However, 1H transverse relaxation and t1-noise often reduce the sensitivity of D-HMQC experiments, preventing the theoretical gains in sensitivity provided by 1H detection from being realized. Here we demonstrate a series of improved pulse sequences for 1H detection of spin-1/2 nuclei under fast MAS, with 195Pt SSNMR experiments on cisplatin as an example. First, a t1-incrementation protocol for D-HMQC dubbed Arbitrary Indirect Dwell (AID) is demonstrated. AID allows the use of arbitrary, rotor asynchronous t1-increments, but removes the constant time period from CT D-HMQC, resulting in improved sensitivity by reducing transverse relaxation losses. Next, we show that short high-power adiabatic pulses (SHAPs), which efficiently invert broad MAS sideband manifolds, can be effectively incorporated into 1H detected symmetry-based resonance echo double resonance (S-REDOR) and t1-noise eliminated (TONE) D-HMQC experiments. The S-REDOR experiments with SHAPs provide approximately double the dipolar dephasing, as compared to experiments with rectangular inversion pulses. We lastly show that sensitivity and resolution can be further enhanced with the use of swept excitation pulses as well as adiabatic magic angle turning (aMAT).
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Affiliation(s)
- Amrit Venkatesh
- US DOE Ames Laboratory, Ames, IA 50011, USA; Iowa State University, Department of Chemistry, Ames, IA 50011, USA
| | | | - Aaron J Rossini
- US DOE Ames Laboratory, Ames, IA 50011, USA; Iowa State University, Department of Chemistry, Ames, IA 50011, USA.
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39
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Carvalho JP, Pell AJ. Frequency-swept adiabatic pulses for broadband solid-state MAS NMR. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 324:106911. [PMID: 33482528 DOI: 10.1016/j.jmr.2020.106911] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/17/2020] [Accepted: 12/25/2020] [Indexed: 06/12/2023]
Abstract
We present a complete description of frequency-swept adiabatic pulses applied to isolated spin-1/2 nuclei with a shift anisotropy in solid materials under magic-angle spinning. Our theoretical framework unifies the existing descriptions of adiabatic pulses in the high-power regime, where the radiofrequency (RF) amplitude is greater than twice the spinning frequency, and the low-power regime, where the RF power is less than the spinning frequency, and so links the short high-powered adiabatic pulse (SHAP) and single-sideband-selective adiabatic pulses (S3AP) schemes used in paramagnetic solid-state NMR. We also identify a hitherto unidentified third regime intermediate between the low- and high-power regimes, and separated from them by rotary resonance conditions. We show that the prevailing benchmark of inversion performance based on (super) adiabatic factors is only applicable in the high- and intermediate-power regimes, but fails to account both for the poor performance at rotary resonance, and the impressive inversion seen in the low-power regime. For low-power pulses, which are non-adiabatic according to this definition of (super) adiabaticity, the effective Floquet Hamiltonian in the jolting frame reveals "hidden" (super) adiabaticity. The theory is demonstrated using a combination of simulation and experiment, and is used to refine the practical recommendations for the experimentalist who wishes to use these pulses.
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Affiliation(s)
- José P Carvalho
- Materials and Environmental Chemistry, Stockholm University, Svänte Arrhenius väg 16 C 106 91, Stockholm, Sweden
| | - Andrew J Pell
- Materials and Environmental Chemistry, Stockholm University, Svänte Arrhenius väg 16 C 106 91, Stockholm, Sweden; Centre de RMN Trés Hauts Champs de Lyon (FRE 2034 - CNRS, ENS Lyon, UCB Lyon 1), Université de Lyon, 5 rue de la Doua, 69100 Villeurbanne, France.
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40
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Shi M, Jin X, Wan Z, He X. Automated fragmentation quantum mechanical calculation of 13C and 1H chemical shifts in molecular crystals. J Chem Phys 2021; 154:064502. [PMID: 33588539 DOI: 10.1063/5.0039115] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In this work, the automated fragmentation quantum mechanics/molecular mechanics (AF-QM/MM) approach was applied to calculate the 13C and 1H nuclear magnetic resonance (NMR) chemical shifts in molecular crystals. Two benchmark sets of molecular crystals were selected to calculate the NMR chemical shifts. Systematic investigation was conducted to examine the convergence of AF-QM/MM calculations and the impact of various density functionals with different basis sets on the NMR chemical shift prediction. The result demonstrates that the calculated NMR chemical shifts are close to convergence when the distance threshold for the QM region is larger than 3.5 Å. For 13C chemical shift calculations, the mPW1PW91 functional is the best density functional among the functionals chosen in this study (namely, B3LYP, B3PW91, M06-2X, M06-L, mPW1PW91, OB98, and OPBE), while the OB98 functional is more suitable for the 1H NMR chemical shift prediction of molecular crystals. Moreover, with the B3LYP functional, at least a triple-ζ basis set should be utilized to accurately reproduce the experimental 13C and 1H chemical shifts. The employment of diffuse basis functions will further improve the accuracy for 13C chemical shift calculations, but not for the 1H chemical shift prediction. We further proposed a fragmentation scheme of dividing the central molecule into smaller fragments. By comparing with the results of the fragmentation scheme using the entire central molecule as the core region, the AF-QM/MM calculations with the fragmented central molecule can not only achieve accurate results but also reduce the computational cost. Therefore, the AF-QM/MM approach is capable of predicting the 13C and 1H NMR chemical shifts for molecular crystals accurately and effectively, and could be utilized for dealing with more complex periodic systems such as macromolecular polymers and biomacromolecules. The AF-QM/MM program for molecular crystals is available at https://github.com/shiman1995/NMR.
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Affiliation(s)
- Man Shi
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Xinsheng Jin
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Zheng Wan
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Xiao He
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
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41
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Altenhof AR, Jaroszewicz MJ, Harris KJ, Schurko RW. Broadband adiabatic inversion experiments for the measurement of longitudinal relaxation time constants. J Chem Phys 2021; 154:034202. [PMID: 33499635 DOI: 10.1063/5.0039017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Accurate measurements of longitudinal relaxation time constants (T1) in solid-state nuclear magnetic resonance (SSNMR) experiments are important for the study of molecular-level structure and dynamics. Such measurements are often made under magic-angle spinning conditions; however, there are numerous instances where they must be made on stationary samples, which often give rise to broad powder patterns arising from large anisotropic NMR interactions. In this work, we explore the use of wideband uniform-rate smooth-truncation pulses for the measurement of T1 constants. Two experiments are introduced: (i) BRAIN-CPT1, a modification of the BRAIN-CP (BRoadband Adiabatic-INversion-Cross Polarization) sequence, for broadband CP-based T1 measurements and (ii) WCPMG-IR, a modification of the WURST-CPMG sequence, for direct-excitation (DE) inversion-recovery experiments. A series of T1 constants are measured for spin-1/2 and quadrupolar nuclei with broad powder patterns, such as 119Sn (I = 1/2), 35Cl (I = 3/2), 2H (I = 1), and 195Pt (I = 1/2). High signal-to-noise spectra with uniform patterns can be obtained due to signal enhancements from T2 eff-weighted echo trains, and in favorable cases, BRAIN-CPT1 allows for the rapid measurement of T1 in comparison to DE experiments. Protocols for spectral acquisition, processing, and analysis of relaxation data are discussed. In most cases, relaxation behavior can be modeled with either monoexponential or biexponential functions based upon measurements of integrated powder pattern intensity; however, it is also demonstrated that one must interpret such T1 values with caution, as demonstrated by measurements of T1 anisotropy in 119Sn, 2H, and 195Pt NMR spectra.
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Affiliation(s)
- Adam R Altenhof
- National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, USA
| | - Michael J Jaroszewicz
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario N9B 3P4, Canada
| | - Kristopher J Harris
- Department of Chemistry, Louisiana Tech University, Ruston, Louisiana 71272, USA
| | - Robert W Schurko
- National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, USA
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42
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Reif B, Ashbrook SE, Emsley L, Hong M. Solid-state NMR spectroscopy. NATURE REVIEWS. METHODS PRIMERS 2021; 1:2. [PMID: 34368784 PMCID: PMC8341432 DOI: 10.1038/s43586-020-00002-1] [Citation(s) in RCA: 155] [Impact Index Per Article: 51.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/29/2020] [Indexed: 12/18/2022]
Abstract
Solid-state nuclear magnetic resonance (NMR) spectroscopy is an atomic-level method used to determine the chemical structure, three-dimensional structure, and dynamics of solids and semi-solids. This Primer summarizes the basic principles of NMR as applied to the wide range of solid systems. The fundamental nuclear spin interactions and the effects of magnetic fields and radiofrequency pulses on nuclear spins are the same as in liquid-state NMR. However, because of the anisotropy of the interactions in the solid state, the majority of high-resolution solid-state NMR spectra is measured under magic-angle spinning (MAS), which has profound effects on the types of radiofrequency pulse sequences required to extract structural and dynamical information. We describe the most common MAS NMR experiments and data analysis approaches for investigating biological macromolecules, organic materials, and inorganic solids. Continuing development of sensitivity-enhancement approaches, including 1H-detected fast MAS experiments, dynamic nuclear polarization, and experiments tailored to ultrahigh magnetic fields, is described. We highlight recent applications of solid-state NMR to biological and materials chemistry. The Primer ends with a discussion of current limitations of NMR to study solids, and points to future avenues of development to further enhance the capabilities of this sophisticated spectroscopy for new applications.
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Affiliation(s)
- Bernd Reif
- Technische Universität München, Department Chemie, Lichtenbergstr. 4, D-85747 Garching, Germany
| | - Sharon E. Ashbrook
- School of Chemistry, University of St Andrews, North Haugh, St Andrews, KY16 9ST, UK
| | - Lyndon Emsley
- École Polytechnique Fédérale de Lausanne (EPFL), Institut des sciences et ingénierie chimiques, CH-1015 Lausanne, Switzerland
| | - Mei Hong
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, 170 Albany Street, Cambridge, MA 02139
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43
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Venkatesh A, Lund A, Rochlitz L, Jabbour R, Gordon CP, Menzildjian G, Viger-Gravel J, Berruyer P, Gajan D, Copéret C, Lesage A, Rossini AJ. The Structure of Molecular and Surface Platinum Sites Determined by DNP-SENS and Fast MAS 195Pt Solid-State NMR Spectroscopy. J Am Chem Soc 2020; 142:18936-18945. [DOI: 10.1021/jacs.0c09101] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Amrit Venkatesh
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
- US DOE Ames Laboratory, Ames, Iowa 50011, United States
| | - Alicia Lund
- Univ Lyon, ENS Lyon, Université Lyon 1, CNRS, High-Field NMR Center of Lyon, FRE 2034, F-69100 Villeurbanne, France
| | - Lukas Rochlitz
- Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Ribal Jabbour
- Univ Lyon, ENS Lyon, Université Lyon 1, CNRS, High-Field NMR Center of Lyon, FRE 2034, F-69100 Villeurbanne, France
| | - Christopher P. Gordon
- Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Georges Menzildjian
- Univ Lyon, ENS Lyon, Université Lyon 1, CNRS, High-Field NMR Center of Lyon, FRE 2034, F-69100 Villeurbanne, France
| | - Jasmine Viger-Gravel
- Univ Lyon, ENS Lyon, Université Lyon 1, CNRS, High-Field NMR Center of Lyon, FRE 2034, F-69100 Villeurbanne, France
- Department of Organic Chemistry, University of Geneva, 1211 Geneva, Switzerland
| | - Pierrick Berruyer
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - David Gajan
- Univ Lyon, ENS Lyon, Université Lyon 1, CNRS, High-Field NMR Center of Lyon, FRE 2034, F-69100 Villeurbanne, France
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Anne Lesage
- Univ Lyon, ENS Lyon, Université Lyon 1, CNRS, High-Field NMR Center of Lyon, FRE 2034, F-69100 Villeurbanne, France
| | - Aaron J. Rossini
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
- US DOE Ames Laboratory, Ames, Iowa 50011, United States
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44
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Yamada K, Yamaguchi T, Ohashi R, Ohki S, Deguchi K, Hashi K, Goto A, Shimizu T. Field-stepwise-swept QCPMG solid-state 115In NMR of indium oxide. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2020; 109:101688. [PMID: 32947243 DOI: 10.1016/j.ssnmr.2020.101688] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 08/25/2020] [Accepted: 08/25/2020] [Indexed: 06/11/2023]
Abstract
Experimental and theoretical investigations of indium-115 electric-field-gradient (EFG) tensors of indium(III) oxide, In2O3, have been presented. Field-stepwise-swept QCPMG solid-state 115In NMR experiments are carried out at T = 120 K, observed at 52.695 MHz, and in the range of external magnetic fields between 4.0 and 6.5 T. The spectral simulations yield the quadrupolar coupling constant, CQ value, of 183(2) MHz and the asymmetry parameter, ηQ, of 0.05(5), for In(1), and that of 126(2) MHz and ηQ of 0.86(5) for In(2). Quantum chemical calculations are carried out to provide 115In EFG tensor orientations with respect to the molecular structure. A relationship between operative frequencies and variable ranges of external magnetic fields is briefly discussed for field-swept solid-state 115In NMR.
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Affiliation(s)
- Kazuhiko Yamada
- Interdisciplinary Science Unit, Multidisciplinary Sciences Cluster, Research and Education Faculty, Kochi University, Nankoku City, Kochi 783-8505, Japan.
| | - Takumi Yamaguchi
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
| | - Ryutaro Ohashi
- National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan; Department of Chemistry, Graduate School of Natural Science & Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Shinobu Ohki
- National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
| | - Kenzo Deguchi
- National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
| | - Kenjiro Hashi
- National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
| | - Atsushi Goto
- National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
| | - Tadashi Shimizu
- National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
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45
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Wijesekara AV, Venkatesh A, Lampkin BJ, VanVeller B, Lubach JW, Nagapudi K, Hung I, Gor'kov PL, Gan Z, Rossini AJ. Fast Acquisition of Proton-Detected HETCOR Solid-State NMR Spectra of Quadrupolar Nuclei and Rapid Measurement of NH Bond Lengths by Frequency Selective HMQC and RESPDOR Pulse Sequences. Chemistry 2020; 26:7881-7888. [PMID: 32315472 DOI: 10.1002/chem.202000390] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 04/20/2020] [Indexed: 12/14/2022]
Abstract
Fast magic-angle spinning (MAS), frequency selective (FS) heteronuclear multiple quantum coherence (HMQC) experiments which function in an analogous manner to solution SOFAST HMQC NMR experiments, are demonstrated. Fast MAS enables efficient FS excitation of 1 H solid-state NMR signals. Selective excitation and observation preserves 1 H magnetization, leading to a significant shortening of the optimal inter-scan delay. Dipolar and scalar 1 H{14 N} FS HMQC solid-state NMR experiments routinely provide 4- to 9-fold reductions in experiment times as compared to conventional 1 H{14 N} HMQC solid-state NMR experiments. 1 H{14 N} FS resonance-echo saturation-pulse double-resonance (RESPDOR) allowed dipolar dephasing curves to be obtained in minutes, enabling the rapid determination of NH dipolar coupling constants and internuclear distances. 1 H{14 N} FS RESPDOR was used to assign multicomponent active pharmaceutical ingredients (APIs) as salts or cocrystals. FS HMQC also provided enhanced sensitivity for 1 H{17 O} and 1 H{35 Cl} HMQC experiments on 17 O-labeled Fmoc-alanine and histidine hydrochloride monohydrate, respectively. FS HMQC and FS RESPDOR experiments will provide access to valuable structural constraints from materials that are challenging to study due to unfavorable relaxation times or dilution of the nuclei of interest.
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Affiliation(s)
- Anuradha V Wijesekara
- Department of Chemistry, Iowa State University, Ames, IA, 50011, USA.,US DOE Ames Laboratory, Ames, IA, 50011, USA
| | - Amrit Venkatesh
- Department of Chemistry, Iowa State University, Ames, IA, 50011, USA.,US DOE Ames Laboratory, Ames, IA, 50011, USA
| | - Bryan J Lampkin
- Department of Chemistry, Iowa State University, Ames, IA, 50011, USA
| | - Brett VanVeller
- Department of Chemistry, Iowa State University, Ames, IA, 50011, USA
| | | | | | - Ivan Hung
- Center of Interdisciplinary Magnetic Resonance (CIMAR), National High Magnetic Field Laboratory (NHMFL), Tallahassee, FL, 32310, USA
| | - Peter L Gor'kov
- Center of Interdisciplinary Magnetic Resonance (CIMAR), National High Magnetic Field Laboratory (NHMFL), Tallahassee, FL, 32310, USA
| | - Zhehong Gan
- Center of Interdisciplinary Magnetic Resonance (CIMAR), National High Magnetic Field Laboratory (NHMFL), Tallahassee, FL, 32310, USA
| | - Aaron J Rossini
- Department of Chemistry, Iowa State University, Ames, IA, 50011, USA.,US DOE Ames Laboratory, Ames, IA, 50011, USA
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46
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Liaghati Mobarhan Y, Soong R, Lane D, Simpson AJ. In vivo comprehensive multiphase NMR. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2020; 58:427-444. [PMID: 32239574 DOI: 10.1002/mrc.4832] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 12/20/2018] [Accepted: 01/03/2019] [Indexed: 06/11/2023]
Abstract
Traditionally, due to different hardware requirements, nuclear magnetic resonance (NMR) has developed as two separate fields: one dealing with solids, and one with solutions. Comprehensive multiphase (CMP) NMR combines all electronics and hardware (magic angle spinning [MAS], gradients, high power Radio Frequency (RF) handling, lock, susceptibility matching) into a universal probe that permits a comprehensive study of all phases (i.e., liquid, gel-like, semisolid, and solid), in intact samples. When applied in vivo, it provides unique insight into the wide array of bonds in a living system from the most mobile liquids (blood, fluids) through gels (muscle, tissues) to the most rigid (exoskeleton, shell). In this tutorial, the practical aspects of in vivo CMP NMR are discussed including: handling the organisms, rotor preparation, sample spinning, water suppression, editing experiments, and finishes with a brief look at the potential of other heteronuclei (2 H, 15 N, 19 F, 31 P) for in vivo research. The tutorial is aimed as a general resource for researchers interested in developing and applying MAS-based approaches to living organisms. Although the focus here is CMP NMR, many of the approaches can be adapted (or directly applied) using conventional high-resolution magic angle spinning, and in some cases, even standard solid-state NMR probes.
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Affiliation(s)
- Yalda Liaghati Mobarhan
- Environmental NMR Center, Department of Physical and Environmental Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Ronald Soong
- Environmental NMR Center, Department of Physical and Environmental Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Daniel Lane
- Environmental NMR Center, Department of Physical and Environmental Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Andre J Simpson
- Environmental NMR Center, Department of Physical and Environmental Sciences, University of Toronto, Toronto, Ontario, Canada
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47
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Koppe J, Hansen MR. Minimizing Lineshape Distortions in Static Ultra-wideline Nuclear Magnetic Resonance of Half-Integer Spin Quadrupolar Nuclei. J Phys Chem A 2020; 124:4314-4321. [DOI: 10.1021/acs.jpca.0c03658] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jonas Koppe
- Institute for Physical Chemistry, Westfälische Wilhelms-Universität, Corrensstr. 28/30, DE-48149 Münster, Germany
| | - Michael Ryan Hansen
- Institute for Physical Chemistry, Westfälische Wilhelms-Universität, Corrensstr. 28/30, DE-48149 Münster, Germany
- Center for Multiscale Theory and Computation (CMTC), Westfälische Wilhelms-Universität, Corrensstrasse 40, D-48149 Münster, Germany
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48
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Zhao D, Shen X, Cheng Z, Li W, Dong H, Li S. Accurate and Efficient Prediction of NMR Parameters of Condensed-Phase Systems with the Generalized Energy-Based Fragmentation Method. J Chem Theory Comput 2020; 16:2995-3005. [DOI: 10.1021/acs.jctc.9b01298] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Dongbo Zhao
- School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, People’s Republic of China
- Kuang Yaming Honors School, Nanjing University, 210023 Nanjing, People’s Republic of China
| | - Xiaoling Shen
- School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, People’s Republic of China
| | - Zheng Cheng
- School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, People’s Republic of China
| | - Wei Li
- School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, People’s Republic of China
| | - Hao Dong
- Kuang Yaming Honors School, Nanjing University, 210023 Nanjing, People’s Republic of China
- Institute for Brain Sciences, Nanjing University, 210023 Nanjing, People’s Republic of China
| | - Shuhua Li
- School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, People’s Republic of China
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49
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Culver DB, Huynh W, Tafazolian H, Conley MP. Solid-State 45Sc NMR Studies of Cp* 2Sc–OR (R = CMe 2CF 3, CMe(CF 3) 2, C(CF 3) 3, SiPh 3) and Relationship to the Structure of Cp* 2Sc-Sites Supported on Partially Dehydroxylated Silica. Organometallics 2020. [DOI: 10.1021/acs.organomet.9b00840] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Damien B. Culver
- Department of Chemistry, University of California, Riverside, California 92521, United States
| | - Winn Huynh
- Department of Chemistry, University of California, Riverside, California 92521, United States
| | - Hosein Tafazolian
- Department of Chemistry, University of California, Riverside, California 92521, United States
| | - Matthew P. Conley
- Department of Chemistry, University of California, Riverside, California 92521, United States
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50
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Charles P, Kalendra V, He Z, Khatami MH, Golbeck JH, van der Est A, Lakshmi KV, Bryant DA. Two-dimensional 67Zn HYSCORE spectroscopy reveals that a Zn-bacteriochlorophyll aP′ dimer is the primary donor (P840) in the type-1 reaction centers of Chloracidobacterium thermophilum. Phys Chem Chem Phys 2020; 22:6457-6467. [DOI: 10.1039/c9cp06556c] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Using pulsed EPR spectroscopy and isotopic labeling we demonstrate that reaction centers of Chloracidobacterium thermophilum have an unusual primary donor that is a dimer of Zn-bacteriochlorophyll aP′ molecules.
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Affiliation(s)
- Philip Charles
- Departments of Chemistry and Physics and The Baruch ’60 Center for Biochemical Solar Energy Research
- Rensselaer Polytechnic Institute
- Troy
- USA
| | - Vidmantas Kalendra
- Departments of Chemistry and Physics and The Baruch ’60 Center for Biochemical Solar Energy Research
- Rensselaer Polytechnic Institute
- Troy
- USA
| | - Zhihui He
- Department of Biochemistry and Molecular Biology
- The Pennsylvania State University
- State College
- USA
| | | | - John H. Golbeck
- Department of Biochemistry and Molecular Biology
- The Pennsylvania State University
- State College
- USA
- Department of Chemistry
| | | | - K. V. Lakshmi
- Departments of Chemistry and Physics and The Baruch ’60 Center for Biochemical Solar Energy Research
- Rensselaer Polytechnic Institute
- Troy
- USA
| | - Donald A. Bryant
- Department of Biochemistry and Molecular Biology
- The Pennsylvania State University
- State College
- USA
- Department of Chemistry and Biochemistry
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