Spin–lattice relaxation
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A Complete <i>Ab Initio</i> View of Orbach and Raman Spin–Lattice Relaxation in a Dysprosium Coordination Compound Open
The unique electronic and magnetic properties of lanthanide molecular complexes place them at the forefront of the race toward high-temperature single-molecule magnets and magnetic quantum bits. The design of compounds of this class has so…
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Fast Rotational Dynamics in Argyrodite-Type Li<sub>6</sub>PS<sub>5</sub>X (X: Cl, Br, I) as Seen by <sup>31</sup>P Nuclear Magnetic Relaxation—On Cation–Anion Coupled Transport in Thiophosphates Open
Electrolytes with excellent ionic conductivity are needed for the development of safe and long-lasting all-solid-state batteries. Perfect candidates are Argyrodites, like Li6PS5X (X: Cl, Br, I), that show an ionic conductivity in the mS/cm…
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Chemical control of spin–lattice relaxation to discover a room temperature molecular qubit Open
Elucidating the role of specific vibrational modes in spin lattice relaxation is a key step to designing room temperature qubits. We executed an experimental and theoretical study on a series of Cu 2+ qubits to increase their operating tem…
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In vivo estimation of transverse relaxation time constant (T<sub>2</sub>) of 17 human brain metabolites at 3T Open
Purpose The transverse relaxation times T 2 of 17 metabolites in vivo at 3T is reported and region specific differences are addressed. Methods An echo‐time series protocol was applied to one, two, or three volumes of interest with differen…
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Short-range ion dynamics in methylammonium lead iodide by multinuclear solid state NMR and<sup>127</sup>I NQR Open
Extensive NMR measurements reveal ion dynamics in CH3NH3PbI3. Fast, bi-axial reorientation of CH3NH3+identified, alongside strong nuclear Pb–I coupling.
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Spin-lattice relaxation of individual solid-state spins Open
Understanding the effect of vibrations on the relaxation process of\nindividual spins is crucial for implementing nano systems for quantum\ninformation and quantum metrology applications. In this work, we present a\ntheoretical microscopic…
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Slow Magnetic Relaxation in Lanthanoid Crown Ether Complexes: Interplay of Raman and Anomalous Phonon Bottleneck Processes Open
The combination of lanthanoid nitrates with 18‐crown‐6 (18‐c‐6) and tetrahalocatecholate (X 4 Cat 2− , X=Cl, Br) ligands has afforded two compound series [Ln(18‐c‐6)(X 4 Cat)(NO 3 )] ⋅ MeCN (X=Cl, 1‐Ln ; X=Br, 2‐Ln ; Ln=La, Ce, Nd, Gd, Tb,…
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Electron spin dynamics and spin–lattice relaxation of trityl radicals in frozen solutions Open
Self-assembly of trityl radical aggregates dominates electron spin dynamics for dynamic nuclear polarization.
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Spin-lattice relaxation of magnetic centers in molecular crystals at low temperature Open
We study the spin-phonon relaxation rate of both Kramers and non-Kramers molecular magnets in strongly diluted samples at low temperature. Using the "rotational" contribution to the spin-phonon Hamiltonian, universal formulae for the relax…
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Dynamics of Solid Proteins by Means of Nuclear Magnetic Resonance Relaxometry Open
1H Nuclear magnetic resonance (NMR) relaxometry was exploited to investigate the dynamics of solid proteins. The relaxation experiments were performed at 37 °C over a broad frequency range, from approximately 10 kHz to 40 MHz. Two relaxati…
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Is the manifestation of the local dynamics in the spin–lattice NMR relaxation in dendrimers sensitive to excluded volume interactions? Open
The maximum of the spin–lattice NMR relaxation function is shifted (not shifted) towards lower frequencies with increasing distance from terminal groups to the center for semiflexible (flexible) phantom and excluded volume models of dendri…
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Mechanism of Water Dynamics in Hyaluronic Dermal Fillers Revealed by Nuclear Magnetic Resonance Relaxometry Open
1 H spin−lattice nuclear magnetic resonance relaxation experiments were performed for five kinds of dermal fillers based on hyaluronic acid. The relaxation data were collected over a broad frequency range between 4 kHz and 40 MHz, at body …
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Characterization of anomalous relaxation using the time-fractional Bloch equation and multiple echo T<sub>2</sub>*-weighted magnetic resonance imaging at 7 T Open
We were able to fit multiple echo time MRI data with high accuracy using the developed model. Parameters of the model likely capture information on microstructural and susceptibility-induced changes in the human brain. Magn Reson Med 77:14…
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Slow spin relaxation of paramagnetic centers in graphene oxide Open
Paramagnetic centers in graphene oxide (GO) were studied by continuous wave and pulsed electron paramagnetic resonance (EPR) in the temperature range 4.2–300 K. Saturation of the EPR signal indicates long spin relaxation times of the param…
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Dynamics of Ionic Liquids in Confinement by Means of NMR Relaxometry—EMIM-FSI in a Silica Matrix as an Example Open
1H and 19F spin–lattice relaxation studies for 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide in bulk and mesoporous MCM-41 silica matrix confinement were performed under varying temperatures in a broad range of magnetic fields, corr…
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Effects of concentration and vendor specific composition of formalin on postmortem MRI of the human brain Open
Purpose Formalin fixation prevents tissue autolysis by crosslinking proteins and changes tissue microstructure and MRI signal characteristics. Previous studies showed high variations in MR relaxation time constants of formalin fixed brain …
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Human whole blood <sup>1</sup>H<sub>2</sub>O transverse relaxation with gadolinium‐based contrast reagents: Magnetic susceptibility and transmembrane water exchange Open
Purpose To characterize transverse relaxation in oxygenated whole blood with extracellular gadolinium‐based contrast reagents by experiment and simulation. Methods Experimental measurements of transverse 1 H 2 O relaxation from oxygenated …
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Pseudogap Behavior of the Nuclear Spin–Lattice Relaxation Rate in FeSe Probed by <sup>77</sup>Se-NMR Open
We conducted $^{77}$Se-nuclear magnetic resonance studies of the iron-based\nsuperconductor FeSe in magnetic fields of 0.6 to 19 T to investigate the\nsuperconducting and normal-state properties. The nuclear spin-lattice\nrelaxation rate d…
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Nuclear magnetic resonance and nuclear spin relaxation in AlAs quantum well probed by ESR Open
The study of nuclear magnetic resonance and nuclear spin-lattice relaxation\nwas conducted in an asymmetrically doped to $n\\sim1.8\\times10^{11}$ cm$^{-2}$\n16 nm AlAs quantum well grown in the $[001]$-direction. Dynamic polarization of\n…
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Elucidation of the downfield spectrum of human brain at 7 T using multiple inversion recovery delays and echo times Open
Purpose To characterize the downfield spectrum at 5–10 ppm in the human brain at a high magnetic field of 7 T. Knowledge of relaxation parameters is of interest for spectroscopy as well as chemical exchange–dependent saturation transfer ex…
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Inducing Defects in <sup>19</sup>F-Nanocrystals Provides Paramagnetic-free Relaxation Enhancement for Improved <i>In Vivo</i> Hotspot MRI Open
Paramagnetic relaxation enhancement (PRE) is the current strategy of choice for enhancing magnetic resonance imaging (MRI) contrast and for accelerating MRI acquisition schemes. Yet, debates regarding lanthanides' biocompatibility and PRE-…
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Rapid <sup>13</sup>C Hyperpolarization of the TCA Cycle Intermediate α-Ketoglutarate via SABRE-SHEATH Open
α-Ketoglutarate is a key biomolecule involved in a number of metabolic pathways─most notably the TCA cycle. Abnormal α-ketoglutarate metabolism has also been linked with cancer. Here, isotopic labeling was employed to synthesize [1-13C,5-1…
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NMR Lineshapes and Scalar Relaxation of the Water‐Endofullerene H<sub>2</sub><sup>17</sup>O@C<sub>60</sub> Open
The 17 O isotopomer of the water‐endofullerene H 2 O@C 60 displays a remarkable proton NMR spectrum, with six well resolved peaks. These peaks are due to the J ‐coupling between the water protons and the 17 O nucleus, which has spin‐5/2. T…
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Cross-Correlated Relaxation of Dipolar Coupling and Chemical-Shift Anisotropy in Magic-Angle Spinning <i>R</i><sub>1ρ</sub> NMR Measurements: Application to Protein Backbone Dynamics Measurements Open
Transverse relaxation rate measurements in magic-angle spinning solid-state nuclear magnetic resonance provide information about molecular motions occurring on nanosecond-to-millisecond (ns-ms) time scales. The measurement of heteronuclear…
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Field-cycling long-lived-state NMR of <sup>15</sup>N<sub>2</sub> spin pairs Open
A range of nuclear magnetic resonance spectroscopy and imaging applications are limited by the short lifetimes of magnetisation in solution. Long-lived states, which are slowly relaxing configurations of nuclear spins, have been shown to a…
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Short echo time relaxation‐enhanced MR spectroscopy reveals broad downfield resonances Open
Purpose Most MR spectroscopy (MRS) pulse sequences rely on broadband excitation with water saturation and typically focus on upfield signals. By contrast, the downfield spectrum, which contains many potentially useful resonances, is typica…
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A method to calculate the NMR spectra of paramagnetic species using thermalized electronic relaxation Open
For paramagnetic species, it has been long understood that the hyperfine interaction between the unpaired electrons and the nucleus results in a nuclear magnetic resonance (NMR) peak that is shifted by a paramagnetic shift, rather than spl…
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Relaxation‐corrected macromolecular model enables determination of <sup>1</sup>H longitudinal T<sub>1</sub>‐relaxation times and concentrations of human brain metabolites at 9.4T Open
Purpose Ultrahigh field MRS has improved characterization of the neurochemical profile. To compare results obtained at 9.4T to those from lower field strengths, it is of interest to quantify the concentrations of metabolites measured. Thus…
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<span>EPR</span>‐based oximetric imaging: a combination of single point‐based spatial encoding and <span>T</span><sub>1</sub> weighting Open
Purpose Spin‐lattice relaxation rate (R 1 )‐based time‐domain EPR oximetry is reported for in vivo applications using a paramagnetic probe, a trityl‐based Oxo71. Methods The R 1 dependence of the trityl probe Oxo71 on partial oxygen pressu…
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Nuclear spin coherence properties of<sup>151</sup>Eu<sup>3+</sup>and<sup>153</sup>Eu<sup>3+</sup>in a Y<sub>2</sub>O<sub>3</sub>transparent ceramic Open
<p>We have measured inhomogeneous linewidths and coherence times (T<sub>2</sub>) of nuclear spin transitions in a Eu<sup>3+</sup>:Y<sub>2</sub>O<sub>3</sub> transparent ceramic by an al…