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Liu Z, Zhang P. Signature of Scramblon Effective Field Theory in Random Spin Models. PHYSICAL REVIEW LETTERS 2024; 132:060201. [PMID: 38394581 DOI: 10.1103/physrevlett.132.060201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 11/07/2023] [Accepted: 01/19/2024] [Indexed: 02/25/2024]
Abstract
Information scrambling refers to the propagation of information throughout a quantum system. Its study not only contributes to our understanding of thermalization but also has wide implications in quantum information and black hole physics. Recent studies suggest that information scrambling in large-N systems with all-to-all interactions is mediated by collective modes called scramblons. However, a criterion for the validity of scramblon theory in a specific model is still missing. In this work, we address this issue by investigating the signature of the scramblon effective theory in random spin models with all-to-all interactions. We demonstrate that, in scenarios where the scramblon description holds, the late-time operator size distribution can be predicted from its early-time value, requiring no free parameters. As an illustration, we examine whether Brownian circuits exhibit a scramblon description and obtain a positive confirmation both analytically and numerically. Our findings provide a concrete experimental framework for unraveling the scramblon field theory in random spin models using quantum simulators.
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Affiliation(s)
- Zeyu Liu
- Department of Physics, Fudan University, Shanghai, 200438, China
| | - Pengfei Zhang
- Department of Physics, Fudan University, Shanghai, 200438, China
- Center for Field Theory and Particle Physics, Fudan University, Shanghai, 200438, China
- Shanghai Qi Zhi Institute, AI Tower, Xuhui District, Shanghai, 200232, China
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2
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Zhou T, Swingle B. Operator growth from global out-of-time-order correlators. Nat Commun 2023; 14:3411. [PMID: 37296127 DOI: 10.1038/s41467-023-39065-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 05/26/2023] [Indexed: 06/12/2023] Open
Abstract
In chaotic many-body systems, scrambling or the operator growth can be diagnosed by out-of-time-order correlators of local operators. We show that operator growth also has a sharp imprint in out-of-time-order correlators of global operators. In particular, the characteristic spacetime shape of growing local operators can be accessed using global measurements without any local control or readout. Building on an earlier conjectured phase diagram for operator growth in chaotic systems with power-law interactions, we show that existing nuclear spin data for out-of-time-order correlators of global operators are well fit by our theory. We also predict super-polynomial operator growth in dipolar systems in 3d and discuss the potential observation of this physics in future experiments with nuclear spins and ultra-cold polar molecules.
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Affiliation(s)
- Tianci Zhou
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA, 93106, USA.
- Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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Mahesh TS, Khurana D, Krithika VR, Sreejith GJ, Sudheer Kumar CS. Star-topology registers: NMR and quantum information perspectives. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:383002. [PMID: 34161942 DOI: 10.1088/1361-648x/ac0dd3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 06/23/2021] [Indexed: 06/13/2023]
Abstract
Quantum control of large spin registers is crucial for many applications ranging from spectroscopy to quantum information. A key factor that determines the efficiency of a register for implementing a given information processing task is its network topology. One particular type, called star-topology, involves a central qubit uniformly interacting with a set of ancillary qubits. A particular advantage of the star-topology quantum registers is in the efficient preparation of large entangled states, called NOON states, and their generalized variants. Thanks to the robust generation of such correlated states, spectral simplicity, ease of polarization transfer from ancillary qubits to the central qubit, as well as the availability of large spin-clusters, the star-topology registers have been utilized for several interesting applications over the last few years. Here we review some recent progress with the star-topology registers, particularly via nuclear magnetic resonance methods.
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Affiliation(s)
- T S Mahesh
- Department of Physics and NMR Research Center, Indian Institute of Science Education and Research, Pune 411008, India
| | - Deepak Khurana
- Department of Physics and NMR Research Center, Indian Institute of Science Education and Research, Pune 411008, India
| | - V R Krithika
- Department of Physics and NMR Research Center, Indian Institute of Science Education and Research, Pune 411008, India
| | - G J Sreejith
- Department of Physics and NMR Research Center, Indian Institute of Science Education and Research, Pune 411008, India
| | - C S Sudheer Kumar
- Department of Physics and NMR Research Center, Indian Institute of Science Education and Research, Pune 411008, India
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4
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Mattar N, Renard E, Langlois V, Rios de Anda A. Multiscale Network Structure Analysis by Time Domain 1H DQ NMR and DMA of Resorcinol Diglycidyl Ether‐Jeffamine Matrices. ChemistrySelect 2020. [DOI: 10.1002/slct.202002675] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Nour Mattar
- Institut de Chimie et des Matériaux Paris-Est - Université Paris-Est Créteil, UMR 7182 CNRS 2 rue Henri Dunant 94320 Thiais France
| | - Estelle Renard
- Institut de Chimie et des Matériaux Paris-Est - Université Paris-Est Créteil, UMR 7182 CNRS 2 rue Henri Dunant 94320 Thiais France
| | - Valérie Langlois
- Institut de Chimie et des Matériaux Paris-Est - Université Paris-Est Créteil, UMR 7182 CNRS 2 rue Henri Dunant 94320 Thiais France
| | - Agustin Rios de Anda
- Institut de Chimie et des Matériaux Paris-Est - Université Paris-Est Créteil, UMR 7182 CNRS 2 rue Henri Dunant 94320 Thiais France
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Xue K, Dervisoglu R, Sowa H, Andreas LB. Centerband-Only Detection of Exchange NMR with Natural-Abundance Correction Reveals an Expanded Unit Cell in Phenylalanine Crystals. Chemphyschem 2020; 21:1622-1626. [PMID: 32558171 PMCID: PMC7497148 DOI: 10.1002/cphc.202000517] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Indexed: 11/05/2022]
Abstract
The NMR pulse sequence CODEX (centerband-only detection of exchange) is a widely used method to report on the number of magnetically inequivalent spins that exchange magnetization via spin diffusion. For crystals, this rules out certain symmetries, and the rate of equilibration is sensitive to distances. Here we show that for 13 C CODEX, consideration of natural abundance spins is necessary for crystals of high complexity, demonstrated here with the amino acid phenylalanine. The NMR data rule out the C2 space group that was originally reported for phenylalanine, and are only consistent with a larger unit cell containing eight magnetically inequivalent molecules. Such an expanded cell was recently described based on single crystal data. The large unit cell dictates the use of long spin diffusion times of more than 200 seconds, in order to equilibrate over the entire unit cell volume of 1622 Å3 .
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Affiliation(s)
- Kai Xue
- Max Planck Institute for Biophysical ChemistryDepartment of NMR Based Structural BiologyAm Fassberg. 1137077GoettingenGermany
| | - Riza Dervisoglu
- Max Planck Institute for Biophysical ChemistryDepartment of NMR Based Structural BiologyAm Fassberg. 1137077GoettingenGermany
| | - Heidrun Sowa
- Georg-August-University GoettingenDepartment of CrystallographyGoldschmidtstr. 137077GoettingenGermany
| | - Loren B. Andreas
- Max Planck Institute for Biophysical ChemistryDepartment of NMR Based Structural BiologyAm Fassberg. 1137077GoettingenGermany
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6
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Rios de Anda A, Sotta P, Modjinou T, Langlois V, Versace DL, Renard E. Multiscale Structural Characterization of Biobased Diallyl–Eugenol Polymer Networks. Macromolecules 2020. [DOI: 10.1021/acs.macromol.9b02280] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Agustín Rios de Anda
- Institut de Chimie et des Matériaux Paris-Est—Université Paris-Est Créteil, UMR 7182 CNRS, 2 rue Henri Dunant, 94320 Thiais, France
| | - Paul Sotta
- Laboratoire Polymères et Matériaux Avancés, UMR 5268 CNRS-Solvay, Solvay in Axel’One, 87 rue des Freres Perret, 69192 Saint Fons, France
| | - Tina Modjinou
- Institut de Chimie et des Matériaux Paris-Est—Université Paris-Est Créteil, UMR 7182 CNRS, 2 rue Henri Dunant, 94320 Thiais, France
| | - Valérie Langlois
- Institut de Chimie et des Matériaux Paris-Est—Université Paris-Est Créteil, UMR 7182 CNRS, 2 rue Henri Dunant, 94320 Thiais, France
| | - Davy-Louis Versace
- Institut de Chimie et des Matériaux Paris-Est—Université Paris-Est Créteil, UMR 7182 CNRS, 2 rue Henri Dunant, 94320 Thiais, France
| | - Estelle Renard
- Institut de Chimie et des Matériaux Paris-Est—Université Paris-Est Créteil, UMR 7182 CNRS, 2 rue Henri Dunant, 94320 Thiais, France
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Bochkin GA, Fel'dman EB, Lazarev ID, Samoilenko AA, Vasil'ev SG. Orientational dependencies of dynamics and relaxation of multiple quantum NMR coherences in one-dimensional systems. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 301:10-18. [PMID: 30844689 DOI: 10.1016/j.jmr.2019.02.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 02/25/2019] [Accepted: 02/26/2019] [Indexed: 06/09/2023]
Abstract
Dynamics and relaxation, or decoherence, of multiple quantum (MQ) coherences are investigated experimentally and theoretically for different orientations of a single crystal of fluorapatite with respect to the external magnetic field. Dynamics of MQ coherences is studied as a function of the preparation period of the MQ NMR experiment. Their relaxation, or decoherence, during the evolution period is also investigated. Universal curves for dynamics and relaxation are obtained and describe the experimental data for different orientations of the investigated sample. Those curves prove the dipolar nature of the observed relaxation process. The contribution of the heteronuclear interactions to the dipolar relaxation is also investigated. The source of discrepancies between experimental data and theoretical results in the experiments with a large angle between the nuclear spin chains and the external magnetic field are discussed.
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Affiliation(s)
- G A Bochkin
- Institute of Problems of Chemical Physics of Russian Academy of Sciences, Chernogolovka, Moscow Region 142432, Russia
| | - E B Fel'dman
- Institute of Problems of Chemical Physics of Russian Academy of Sciences, Chernogolovka, Moscow Region 142432, Russia
| | - I D Lazarev
- Institute of Problems of Chemical Physics of Russian Academy of Sciences, Chernogolovka, Moscow Region 142432, Russia; Faculty of Fundamental Physical-Chemical Engineering, Lomonosov Moscow State University, GSP-1, Moscow 119991, Russia
| | - A A Samoilenko
- Institute of Problems of Chemical Physics of Russian Academy of Sciences, Chernogolovka, Moscow Region 142432, Russia
| | - S G Vasil'ev
- Institute of Problems of Chemical Physics of Russian Academy of Sciences, Chernogolovka, Moscow Region 142432, Russia.
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8
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Cui J, Li J, Liu X, Peng X, Fu R. Engineering spin Hamiltonians using multiple pulse sequences in solid state NMR spectroscopy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2018; 294:83-92. [PMID: 30015126 DOI: 10.1016/j.jmr.2018.06.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Revised: 06/19/2018] [Accepted: 06/22/2018] [Indexed: 06/08/2023]
Abstract
Multiple pulse sequences are often used to manipulate spin Hamiltonians in solid-state nuclear magnetic resonance spectroscopy. In this paper, we analyze multiple pulse sequences using the well-known average Hamiltonian theory. We first expand the resulting average Hamiltonian into a reachable set of sub-Hamiltonians and then develop a general procedure using both flip-angle and phase of the applied pulses as control variables to select any of those sub-Hamiltonians. We use this method to analyze solid-echo based sequences and to design new proton-proton homonuclear decoupling sequences in static solids. It is found that this newly designed decoupling scheme, in the presence of finite pulse length, effectively suppresses the 1H-1H homonuclear dipolar interactions while establishes variable scaling factors on the heteronuclear dipolar interactions and chemical shift interactions, depending on the flip-angle of the applied pulses. When the pulse flip-angle is close to 54.7°, this sequence possesses a large scaling factor with relatively low average decoupling field. When the pulse flip-angle becomes ∼120°, the scaling factor is almost zero. A static 15N-acetyl-valine crystal sample has been used as an example to confirm and validate the performance of this new decoupling scheme.
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Affiliation(s)
- Jiangyu Cui
- CAS Key Laboratory of Microscale Magnetic Resonance and Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China; Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jun Li
- Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Xiaomei Liu
- CAS Key Laboratory of Microscale Magnetic Resonance and Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China; Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xinhua Peng
- CAS Key Laboratory of Microscale Magnetic Resonance and Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China; Synergetic Innovation Center for Quantum Effects and Applications, Hunan Normal University, Changsha 410081, China; Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Riqiang Fu
- National High Magnetic Field Lab, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA.
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9
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Khitrin AK. Reversibility of dynamics and multiple-quantum coherences. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 92:052903. [PMID: 26651758 DOI: 10.1103/physreve.92.052903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Indexed: 06/05/2023]
Abstract
In spin systems, the decay of the Loschmidt echo in the time-reversal experiment (evolution-perturbation-time-reversed evolution) is linked to the generation of multiple-quantum (MQ) coherences. Unlimited growth of the MQ coherences leads to irreversibility of dynamics. In some cases, one can expect that the deviation of the Loschmidt echo and the second moment of the MQ intensities distribution are linear in time. The criteria of such behavior, called weak irreversibility, are formulated. The proposed approach can be extended beyond spin systems, in order to analyze some general aspects of reversibility of many-body quantum dynamics.
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Affiliation(s)
- A K Khitrin
- Department of Chemistry, Kent State University, Kent, Ohio 44242, USA
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10
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11
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Teymoori G, Pahari B, Viswanathan E, Edén M. Multiple-quantum spin counting in magic-angle-spinning NMR via low-power symmetry-based dipolar recoupling. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2013; 236:31-40. [PMID: 24044967 DOI: 10.1016/j.jmr.2013.08.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 08/05/2013] [Accepted: 08/14/2013] [Indexed: 06/02/2023]
Abstract
By using a symmetry-based R2(8)(1)R2(8)(-1) double-quantum (2Q) dipolar recoupling sequence, we demonstrate high-order multiple-quantum coherence (MQC) excitation at fast magic-angle spinning (MAS) frequencies up to 34 kHz. This scheme combines several attractive features, such as a relatively high dipolar scaling factor, good compensation to rf-errors, isotropic and anisotropic chemical shifts, as well as an ultra-low radio-frequency (rf) power requirement. The latter translates into nutation frequencies below 30 kHz for MAS rates up to 60 kHz, thereby permitting rf application for very long excitation periods without risk of damaging the NMR probehead or sample, while the compensation to chemical shifts improves as the MAS rate increases. (31)P MQC spin counting is demonstrated on powders of calcium hydroxyapatite (Ca5(PO4)3OH) and anhydrous sodium diphosphate (Na4P2O7), from which all even coherence orders up to 30 and 14 were detected, respectively, over the respective MAS ranges of 15-24 kHz and 20-34 kHz. The amplitude distributions among the (31)P MQC orders depend on the precise nutation frequency during recoupling, despite that the highest detected order was relatively insensitive to this parameter. An observed gradual transition from a Gaussian to exponential functionality of the MQC amplitude-profile is discussed in relation to the prevailing approach to derive spin-cluster sizes by fitting the MQC amplitude-distribution to a Gaussian decay, where minor systematic deviations between the model and experimental data are frequently reported.
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Affiliation(s)
- Gholamhasan Teymoori
- Physical Chemistry Division, Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
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12
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Zelenova Y, Morgan SW, Boutis GS. Effects of experimental imperfections on a spin counting experiment. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2013; 53:27-37. [PMID: 23648319 PMCID: PMC3667418 DOI: 10.1016/j.ssnmr.2013.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 03/22/2013] [Accepted: 03/26/2013] [Indexed: 06/02/2023]
Abstract
Spin counting NMR is an experimental technique that allows a determination of the size and time evolution of networks of dipolar coupled nuclear spins. This work reports on an average Hamiltonian treatment of two spin counting sequences and compares the efficiency of the two cycles in the presence of flip errors, RF inhomogeneity, phase transients, phase errors, and offset interactions commonly present in NMR experiments. Simulations on small quantum systems performed using the two cycles reveal the effects of pulse imperfections on the resulting multiple quantum spectra, in qualitative agreement with the average Hamiltonian calculations. Experimental results on adamantane are presented, demonstrating differences in the two sequences in the presence of pulse errors.
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Affiliation(s)
- Yelena Zelenova
- Brooklyn College of The City University of New York, Department of Physics, Brooklyn, NY 11210, United States
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13
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Mogami Y, Noda Y, Ishikawa H, Takegoshi K. A statistical approach for analyzing the development of 1H multiple-quantum coherence in solids. Phys Chem Chem Phys 2013; 15:7403-10. [PMID: 23580152 DOI: 10.1039/c3cp43778g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel statistical approach for analyzing (1)H multiple-quantum (MQ) spin dynamics in so-called spin-counting solid-state NMR experiments is presented. The statistical approach is based on the percolation theory with Monte Carlo methods and is examined by applying it to the experimental results of three solid samples having unique hydrogen arrangement for 1-3 dimensions: the n-alkane/d-urea inclusion complex as a one-dimensional (1D) system, whose (1)H nuclei align approximately in 1D, and magnesium hydroxide and adamantane as a two-dimensional (2D) and a three-dimensional (3D) system, respectively. Four lattice models, linear, honeycomb, square and cubic, are used to represent the (1)H arrangement of the three samples. It is shown that the MQ dynamics in adamantane is consistent with that calculated using the cubic lattice and that in Mg(OH)2 with that calculated using the honeycomb and the square lattices. For n-C20H42/d-urea, these 4 lattice models fail to express its result. It is shown that a more realistic model representing the (1)H arrangement of n-C20H42/d-urea can describe the result. The present approach can thus be used to determine (1)H arrangement in solids.
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Affiliation(s)
- Yuuki Mogami
- Division of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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14
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Gleason KK, Petrich MA, Reimer JA. Hydrogen Microstructure in Amorphous Semiconductors. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-95-171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractThe effects of deposition parameters on the H microstructure of plasma deposited amorphous silicon (a-Si:H) and amorphous silicon carbide (a-SiC:H) are measured via multiple quantum nuclear magnetic resonance (MQ NMR). These studies indicate clusters of 5 to 7H atoms exist in a-Si:H films prepared at temperatures ranging from 113 to 324°C. In the range from 270 to 324°C, only these small clusters exist, but lower temperature films also contain larger clusters. Annealing studies indicate H rearranges in a-Si:H prior to evolution. Deposition temperature and annealing temperature have similar effects on H concentration in a-Si:H, but deposition temperature control the density and microstructure of the film. The addition of dopant atoms also affects the H microstructure, with phosphorous causing larger H clusters to form, and boron reducing clustering in a-Si:H films. This perturbation of the film's microstructure suggests that the effects of dopant addition are more complex in amorphous than in crystalline semiconductors. The concentration of carbon atoms also effects H microstructure of a-SiC:H in a complex way. We surmise that H microstructure, rather than H content, determines amorphous semiconductors properties.
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Dumez JN, Butler MC, Emsley L. Numerical simulation of free evolution in solid-state nuclear magnetic resonance using low-order correlations in Liouville space. J Chem Phys 2010; 133:224501. [DOI: 10.1063/1.3505455] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Dumez JN, Butler MC, Salager E, Elena-Herrmann B, Emsley L. Ab initio simulation of proton spin diffusion. Phys Chem Chem Phys 2010; 12:9172-5. [DOI: 10.1039/c0cp00050g] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Butler MC, Dumez JN, Emsley L. Dynamics of large nuclear-spin systems from low-order correlations in Liouville space. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2009.07.017] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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18
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Suter D, Mahesh TS. Spins as qubits: Quantum information processing by nuclear magnetic resonance. J Chem Phys 2008; 128:052206. [DOI: 10.1063/1.2838166] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Munowitz M, Pines A. Principles and Applications of Multiple-Quantum Nmr. ADVANCES IN CHEMICAL PHYSICS 2007. [DOI: 10.1002/9780470142929.ch1] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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20
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Oligomeric structure, dynamics, and orientation of membrane proteins from solid-state NMR. Structure 2007; 14:1731-40. [PMID: 17161364 DOI: 10.1016/j.str.2006.10.002] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2006] [Revised: 10/01/2006] [Accepted: 10/03/2006] [Indexed: 11/27/2022]
Abstract
Solid-state NMR is a versatile and powerful tool for determining the dynamic structure of membrane proteins at atomic resolution. I review the recent progress in determining the orientation, the internal and global protein dynamics, the oligomeric structure, and the ligand-bound structure of membrane proteins with both alpha-helical and beta sheet conformations. Examples are given that illustrate the insights into protein function that can be gained from the NMR structural information.
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21
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Lee JS, Khitrin AK. Detection of multiple-quantum coherences with projective nuclear magnetic resonance measurement. J Chem Phys 2006; 125:144521. [PMID: 17042623 DOI: 10.1063/1.2357949] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
It is shown that in nuclear magnetic resonance, multiple-quantum (MQ) coherences can be detected "instantly" by exploiting the principle of quantum-mechanical projective measurement. Therefore, the mixing period, which involves collective multispin dynamics and converts MQ coherences into observable single-quantum coherence (magnetization), is not necessary. The experimental examples are given for two finite clusters: benzene in liquid crystal and liquid crystal 4'-n-pentyl-4-cyanobiphenyl, and for solid adamantane with an infinite network of dipolar couplings.
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Affiliation(s)
- Jae-Seung Lee
- Department of Chemistry, Kent State University, Kent, Ohio 44242-0001, USA
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22
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Krojanski HG, Suter D. Reduced decoherence in large quantum registers. PHYSICAL REVIEW LETTERS 2006; 97:150503. [PMID: 17155308 DOI: 10.1103/physrevlett.97.150503] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Indexed: 05/12/2023]
Abstract
Among the biggest obstacles for building larger (and thus more powerful) quantum-information processors is decoherence, the decay of quantum-information by the coupling between the quantum register and its environment. Procedures for reducing decoherence processes will be essential for successful operation of larger quantum processors. We study model quantum registers consisting of up to 4900 qubits and measure their decay as a function of the register size. We demonstrate that appropriate sequences of qubit rotations reduce the coupling between system and environment for all sizes of the quantum register, thus preserving the quantum-information 50 times longer than without decoupling.
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24
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Walls JD, Lin YY. Constants of motion in NMR spectroscopy. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2006; 29:22-9. [PMID: 16257517 DOI: 10.1016/j.ssnmr.2005.09.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2005] [Indexed: 05/05/2023]
Abstract
We present a general method for constructing a subset of the constants of motion in terms of products of spin operators. These operators are then used to give insight into the multi-spin orders comprising the quasi-equilibrium state formed under a Jeener-Broekaert sequence in small, dipolar-coupled, spin systems. We further show that constants of motion that represent single-quantum coherences are present due to the symmetry of the dipolar Hamiltonian under 180 degrees spin rotations, and that such coherences contribute a DC component to the FID which vanishes in the absence of the flip-flop terms and is only present for spin clusters with an odd number of spins.
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Affiliation(s)
- Jamie D Walls
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
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van Beek JD, Meier BH. A DOQSY approach for the elucidation of torsion angle distributions in biopolymers: application to silk. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2006; 178:106-20. [PMID: 16243550 DOI: 10.1016/j.jmr.2005.09.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2005] [Revised: 09/04/2005] [Accepted: 09/07/2005] [Indexed: 05/05/2023]
Abstract
Silk from the wild silkworm Samia cynthia ricini with a molecular mass of about 300kDa consists of alternating repeats of nano-crystalline poly-(Ala) and non-crystalline glycine-rich domains. The backbone torsion angles between pairs of these two amino acids is determined by DOQSY solid-state NMR spectroscopy: the alanine-rich domains are predominantly in a beta-sheet conformation, whereas the glycine-rich domains are found to be partially in an extended beta-sheet conformation and partially in an approximately 3(1)-helical conformation. In the cast film from liquid silk significantly different secondary structures were found: the alanine-rich domains are alpha-helical conformation, whereas the results for glycine-labelled sample are explained by a random-coil state. A detailed error analysis of the technique is presented.
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26
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Doronin SI, Fel'dman EB. Multiple-quantum NMR spin dynamics of inhomogeneous one-dimensional systems in solids. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2005; 28:111-6. [PMID: 16051472 DOI: 10.1016/j.ssnmr.2005.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2005] [Revised: 06/24/2005] [Accepted: 06/28/2005] [Indexed: 05/03/2023]
Abstract
Multiple-quantum NMR spin dynamics of inhomogeneous one-dimensional systems in solids is investigated by analytical and numerical methods. A fermion approach for MQ spin dynamics of one-dimensional inhomogeneous systems is developed in the approximation of the dipole-dipole interactions (DDI) of nearest neighbors. It is shown that only MQ coherences of the zeroth and plus/minus second orders appear in the approximation of the DDI of the nearest neighbors even in inhomogeneous one-dimensional systems. We also investigate MQ dynamics of inhomogeneous chains numerically. Intensities of MQ NMR coherences for a linear chain consisting of 3000 spins are calculated.
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Affiliation(s)
- Serge I Doronin
- Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka, 142432, Moscow Region, Russia
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27
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Edén M, Brinkmann A. Triple-quantum dynamics in multiple-spin systems undergoing magic-angle spinning: application to 13C homonuclear correlation spectroscopy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2005; 173:259-279. [PMID: 15780918 DOI: 10.1016/j.jmr.2004.12.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Revised: 12/15/2004] [Indexed: 05/24/2023]
Abstract
We analyze the multiple-quantum dynamics governed by a new homonuclear recoupling strategy effecting an average dipolar Hamiltonian comprising three-spin triple-quantum operators (e.g., S(p)+S(q)+S(r)+) under magic-angle spinning conditions. Analytical expressions are presented for polarization transfer processes in systems of three and four coupled spins-1/2 subject to triple-quantum filtration (3QF), and high-order multiple-quantum excitation is investigated numerically in moderately large clusters, comprising up to seven spins. This recoupling approach gives highly efficient excitation of triple-quantum coherences: ideally, up to 67% of the initial polarization may be recovered by 3QF in three-spin systems in polycrystalline powders. Two homonuclear 2D correlation strategies are demonstrated experimentally on powders of uniformly 13C-labeled alanine and tyrosine: the first correlates the single-quantum spectrum in the first dimension with the corresponding 3QF spectrum along the other. The second protocol correlates triple-quantum coherences with their corresponding single-quantum coherences within triplets of coupled spins.
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Affiliation(s)
- Mattias Edén
- Physical Chemistry Division, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden.
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28
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Cappellaro P, Emerson J, Boulant N, Ramanathan C, Lloyd S, Cory DG. Entanglement assisted metrology. PHYSICAL REVIEW LETTERS 2005; 94:020502. [PMID: 15698155 DOI: 10.1103/physrevlett.94.020502] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2004] [Indexed: 05/24/2023]
Abstract
We propose a new approach to the measurement of a single spin state, based on nuclear magnetic resonance (NMR) techniques and inspired by the coherent control over many-body systems envisaged by quantum information processing. A single target spin is coupled via the magnetic dipolar interaction to a large ensemble of spins. Applying radio frequency pulses, we can control the evolution so that the spin ensemble reaches one of two orthogonal states whose collective properties differ depending on the state of the target spin and are easily measured. We first describe this measurement process using quantum gates; then we show how equivalent schemes can be defined in terms of the Hamiltonian and thus implemented under conditions of real control, using well established NMR techniques. We demonstrate this method with a proof of principle experiment in ensemble liquid state NMR and simulations for small spin systems.
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Affiliation(s)
- P Cappellaro
- Department of Nuclear Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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29
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Dodd AJ, van Eck ERH. Multiple quantum spin counting techniques with quadrupolar nuclei. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2004; 26:121-131. [PMID: 15388176 DOI: 10.1016/j.ssnmr.2004.04.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2004] [Revised: 03/02/2004] [Indexed: 05/24/2023]
Abstract
Phase incremented and continuous irradiation multiple spin correlation methods are applied to spin [Formula: see text] nuclei with small quadrupole couplings such as (7)Li in LiCl and are shown to successfully produce a coherently coupled dipolar spin network. Application to the analogous Na salt shows successful spin correlation evolving at a slower rate due to the weaker homonuclear dipolar coupling strength between Na nuclei. The results are analysed using a statistical approach. Spin counting is non-trivial as not only multiple quantum coherences between spins are generated but also within the quadrupolar spin levels. Na(2)C(2)O(4) is investigated as a material with non-negligible quadrupole coupling and it is in this limit that the spin correlation techniques are found to break down.
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Affiliation(s)
- Andrew J Dodd
- Centre for Materials Research, School of Physical Sciences, University of Kent, Canterbury, Kent CT2 7NR, UK
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30
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Blümich B, Spiess HW. Two-Dimensional Solid-State NMR Spectroscopy: New Possibilities for the Investigation of the Structure and Dynamics of Solid Polymers [New Analytical Methods (38)]. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/anie.198816551] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Cho H, Cory DG, Ramanathan C. Spin counting experiments in the dipolar-ordered state. J Chem Phys 2003. [DOI: 10.1063/1.1538244] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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32
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33
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Joo CG, Bronstein LM, Karlinsey RL, Zwanziger JW. Structure and ionic interactions of organic-inorganic composite polymer electrolytes studied by solid-state NMR and Raman spectroscopy. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2002; 22:235-246. [PMID: 12469813 DOI: 10.1006/snmr.2002.0083] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Solid-state NMR studies of composite polymer electrolytes are reported. The materials consist of polyethylene oxide and an organic inorganic composite, together with a lithium salt, and are candidates for electrolytes in solid-state lithium ion batteries. Silicon and aluminum MAS and multiple quantum MAS are used to characterize the network character of the organic-inorganic composite, and spin diffusion measurements are used to determine the nanostructure of the polymer/composite blending. Multiple quantum spin counting is used to measure the ion aggregation. The NMR results are supported by Raman spectra, calorimetry, and impedance spectroscopy. From these experiments it is concluded that the composite suppresses polymer crystallization without suppressing its local mobility, and also suppresses the tendency for the ions to aggregate. This polymer composite thus appears very promising for application in lithium ion batteries.
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Affiliation(s)
- Chan Gyu Joo
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, Indiana 47405, USA
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34
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Lim KH, Nguyen T, Mazur T, Wemmer DE, Pines A. Sensitivity enhancement in multiple-quantum NMR experiments with CPMG detection. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2002; 157:160-162. [PMID: 12202146 DOI: 10.1006/jmre.2002.2578] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We present a modified multiple-quantum (MQ) experiment, which implements the Carr-Purcell-Meiboom-Gill (CPMG) detection scheme in the static MQ NMR experiment proposed by W. S. Warren et al. (1980, J. Chem. Phys.73, 2084-2099) and exploited further by O. N. Antzutkin and R. Tycko (1999, J. Chem. Phys.110, 2749-2752). It is demonstrated that a significant enhancement in the sensitivity can be achieved by acquiring echo trains in the MQ experiments for static powder samples. The modified scheme employing the CPMG detection was superior to the original MQ experiment, in particular for the carbonyl carbon with a very large chemical shift anisotropy.
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Affiliation(s)
- Kwang Hun Lim
- Department of Chemistry, University of California at Berkley, California 94720, USA
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35
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Kaji H, Schmidt-Rohr K. Conformation and Dynamics of Atactic Poly(acrylonitrile). 2. Torsion Angle Distributions in Meso Dyads from Two-Dimensional Solid-State Double-Quantum 13C NMR. Macromolecules 2001. [DOI: 10.1021/ma010657k] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hironori Kaji
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan, and Department of Chemistry and Ames Laboratory, Iowa State University, Ames, Iowa 50011
| | - Klaus Schmidt-Rohr
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan, and Department of Chemistry and Ames Laboratory, Iowa State University, Ames, Iowa 50011
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36
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Tycko R. Solid-state nuclear magnetic resonance techniques for structural studies of amyloid fibrils. Methods Enzymol 2001; 339:390-413. [PMID: 11462823 DOI: 10.1016/s0076-6879(01)39324-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- R Tycko
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
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37
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Tycko R. Biomolecular solid state NMR: advances in structural methodology and applications to peptide and protein fibrils. Annu Rev Phys Chem 2001; 52:575-606. [PMID: 11326075 DOI: 10.1146/annurev.physchem.52.1.575] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Solid state nuclear magnetic resonance (NMR) methods can provide atomic-level structural constraints on peptides and proteins in forms that are not amenable to characterization by other high-resolution structural techniques, owing to insolubility, high molecular weight, noncrystallinity, or other characteristics. Important examples include peptide and protein fibrils and membrane-bound peptides and proteins. Recent advances in solid state NMR methodology aimed at structural problems in biological systems are reviewed. The power of these methods is illustrated by experimental results on amyloid fibrils and other protein fibrils.
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Affiliation(s)
- R Tycko
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0520, USA.
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38
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Tomaselli M, Meier BH, Riccò M, Shiroka T, Sartori A. A multiple-quantum nuclear magnetic resonance study of interstitial Li clusters in LixC60. J Chem Phys 2001. [DOI: 10.1063/1.1377014] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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39
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Michal CA, Tycko R. Time-reversal of the evolution of a dipole-coupled, many-spin system under continuous resonant irradiation. J Chem Phys 2001. [DOI: 10.1063/1.1330239] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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40
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Antzutkin ON, Balbach JJ, Leapman RD, Rizzo NW, Reed J, Tycko R. Multiple quantum solid-state NMR indicates a parallel, not antiparallel, organization of beta-sheets in Alzheimer's beta-amyloid fibrils. Proc Natl Acad Sci U S A 2000; 97:13045-50. [PMID: 11069287 PMCID: PMC27175 DOI: 10.1073/pnas.230315097] [Citation(s) in RCA: 324] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Senile plaques associated with Alzheimer's disease contain deposits of fibrils formed by 39- to 43-residue beta-amyloid peptides with possible neurotoxic effects. X-ray diffraction measurements on oriented fibril bundles have indicated an extended beta-sheet structure for Alzheimer's beta-amyloid fibrils and other amyloid fibrils, but the supramolecular organization of the beta-sheets and other structural details are not well established because of the intrinsically noncrystalline, insoluble nature of amyloid fibrils. Here we report solid-state NMR measurements, using a multiple quantum (MQ) (13)C NMR technique, that probe the beta-sheet organization in fibrils formed by the full-length, 40-residue beta-amyloid peptide (Abeta(1-40)). Although an antiparallel beta-sheet organization often is assumed and is invoked in recent structural models for full-length beta-amyloid fibrils, the MQNMR data indicate an in-register, parallel organization. This work provides site-specific, atomic-level structural constraints on full-length beta-amyloid fibrils and applies MQNMR to a significant problem in structural biology.
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Affiliation(s)
- O N Antzutkin
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, USA
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41
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Abstract
Amyloid fibrils are intrinsically noncrystalline, insoluble, high-molecular-weight aggregates of peptides and proteins, with considerable biomedical and biophysical significance. Solid-state NMR techniques are uniquely capable of providing high-resolution, site-specific structural constraints for amyloid fibrils, at the level of specific interatomic distances and torsion angles. So far, a relatively small number of solid-state NMR studies of amyloid fibrils have been reported. These have addressed issues about the supramolecular organization of beta-sheets in the fibrils and the peptide conformation in the fibrils, and have concentrated on the beta-amyloid peptide of Alzheimer's disease. Many additional applications of solid-state NMR to amyloid fibrils from a variety of sources are anticipated in the near future, as these systems are ideally suited for the technique and are of widespread current interest.
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Affiliation(s)
- R Tycko
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0520, USA.
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42
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van Beek JD, Beaulieu L, Schäfer H, Demura M, Asakura T, Meier BH. Solid-state NMR determination of the secondary structure of Samia cynthia ricini silk. Nature 2000; 405:1077-9. [PMID: 10890452 DOI: 10.1038/35016625] [Citation(s) in RCA: 167] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Silks are fibrous proteins that form heterogeneous, semi-crystalline solids. Silk proteins have a variety of physical properties reflecting their range of functions. Spider dragline silk, for example, has high tensile strength and elasticity, whereas other silks are better suited to making housing, egg sacs or the capture spiral of spiders' webs. The differing physical properties arise from variation in the protein's primary and secondary structure, and their packing in the solid phase. The high mechanical performance of spider dragline silk, for example, is probably due to a beta-sheet conformation of poly-alanine domains, embedded as small crystallites within the fibre. Only limited structural information can be obtained from diffraction of silks, so further characterization requires spectroscopic studies such as NMR. However, the classical approach to NMR structure determination fails because the high molecular weight, repetitive primary structure and structural heterogeneity of solid silk means that signals from individual amino-acid residues cannot be resolved. Here we adapt a recently developed solid-state NMR technique to determine torsion angle pairs (phi, psi) in the protein backbone, and we study the distribution of conformations in silk from the Eri silkworm, Samia cynthia ricini. Although the most probable conformation in native fibres is an anti-parallel beta-sheet, film produced from liquid directly extracted from the silk glands appears to be primarily alpha-helical.
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Affiliation(s)
- J D van Beek
- Laboratory for Physical Chemistry, ETH Zürich, Switzerland
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43
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Brinkmann A, Edén M, Levitt MH. Synchronous helical pulse sequences in magic-angle spinning nuclear magnetic resonance: Double quantum recoupling of multiple-spin systems. J Chem Phys 2000. [DOI: 10.1063/1.481458] [Citation(s) in RCA: 177] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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44
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Carravetta M, Edén M, Zhao X, Brinkmann A, Levitt MH. Symmetry principles for the design of radiofrequency pulse sequences in the nuclear magnetic resonance of rotating solids. Chem Phys Lett 2000. [DOI: 10.1016/s0009-2614(00)00340-7] [Citation(s) in RCA: 290] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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45
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Lacelle S. Article. CAN J CHEM 1999. [DOI: 10.1139/v99-150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The behavior of multiple spin dynamics under time-reversal excitation is investigated in strongly dipolar coupled spin networks. It is demonstrated that the typical physical intuition that NMR spectroscopists have of time-reversal in such systems is erroneous. By studying the equation of motion of the spin system in an infinite one-dimensional quantum spin chain with nearest-neighbor dipolar interactions and evolving under time-reversal excitation, a more appropriate physical picture emerges. Implications of these new findings are briefly discussed in the context of error propagation and teleportation in NMR quantum information processing.Key words: time-reversal, NMR, nuclear spin dynamic, quantum information processing.
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46
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Tycko R. Selection rules for multiple quantum NMR excitation in solids: derivation from time-reversal symmetry and comparison with simulations and (13)C NMR experiments. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 1999; 139:302-307. [PMID: 10423367 DOI: 10.1006/jmre.1999.1776] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
New derivations of selection rules for excitation and detection of multiple quantum coherences in coupled spin-1/2 systems are presented. The selection rules apply to experiments in which the effective coupling Hamiltonian used for multiple quantum excitation is both time-reversal invariant and time-reversible by a phase shift of the radiofrequency pulse sequence that generates the effective couplings. The selection rules are shown to be consequences of time-reversal invariance and time-reversibility and otherwise independent of the specific form of the effective coupling Hamiltonian. Numerical simulations of multiple quantum NMR signal amplitudes and experimental multiple quantum excitation spectra are presented for the case of a multiply (13)C-labeled helical polypeptide. The simulations and experiments confirm the selection rules and demonstrate their impact on multiple quantum (13)C NMR spectra in this biochemically relevant case.
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Affiliation(s)
- R Tycko
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0520, USA.
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47
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Antzutkin ON, Tycko R. High-order multiple quantum excitation in 13C nuclear magnetic resonance spectroscopy of organic solids. J Chem Phys 1999. [DOI: 10.1063/1.477876] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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48
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Ba Y, Ripmeester JA. Multiple quantum filtering and spin exchange in solid state nuclear magnetic resonance. J Chem Phys 1998. [DOI: 10.1063/1.476288] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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49
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Fel’dman EB, Lacelle S. Multiple quantum nuclear magnetic resonance in one-dimensional quantum spin chains. J Chem Phys 1997. [DOI: 10.1063/1.474949] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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50
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Buntkowsky G, Roessler E, Taupitz M, Vieth HM. Adamantane as a Probe for Studies of Spin Clustering with Multiple Quantum NMR. J Phys Chem A 1997. [DOI: 10.1021/jp960963d] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- G. Buntkowsky
- Institut für organische Chemie and Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany, and Physikalisches Institut, Universität Bayreuth, 95440 Bayreuth, Germany
| | - E. Roessler
- Institut für organische Chemie and Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany, and Physikalisches Institut, Universität Bayreuth, 95440 Bayreuth, Germany
| | - M. Taupitz
- Institut für organische Chemie and Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany, and Physikalisches Institut, Universität Bayreuth, 95440 Bayreuth, Germany
| | - H. M. Vieth
- Institut für organische Chemie and Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany, and Physikalisches Institut, Universität Bayreuth, 95440 Bayreuth, Germany
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