Electron spin-lattice relaxation (SLR) of TEMPO radical was measured in the crystalline and glassy states of deuterated ethanol in the temperature range 5-80K using X-band electron paramagnetic resonance (EPR). The measured SLR rates are higher in the glassy than in crystalline state and the excess SLR rate in glassy state is much lower than in ethanol. This result suggests that extra modes in glassy state, i.e. glassy modes, produce the excess SLR rate via the electron-nuclear dipolar (END) interaction between the electron spin of radical and the matrix protons or deuterons. Using the soft-potential model and assuming the END interaction between the electron spin and the matrix protons, the contributions to SLR rate of various mechanisms of glassy modes were theoretically analyzed. The evaluations of SLR rates in glassy ethanol indicate two main mechanisms of glassy modes: thermally activated relaxation of double-well systems and phonon-induced relaxation of quasi-harmonic local modes. The SLR rates induced by these mechanisms correlate well with the experimental data.
Effect of freezing conditions on distances and their distributions derived from Double Electron Electron Resonance (DEER): A study of doubly-spin-labeled T4 lysozyme
Effect of freezing conditions on distances and their distributions derived from Double Electron Electron Resonance (DEER): A study of doubly-spin-labeled T4 lysozyme
Publication year: 2012
Source:Journal of Magnetic Resonance, Volume 216</br>
Elka R. Georgieva, Aritro S. Roy, Vladimir M. Grigoryants, Petr P. Borbat, Keith A. Earle, Charles P. Scholes, Jack H. Freed</br>
Pulsed dipolar ESR spectroscopy, DEER and DQC, require frozen samples. An important issue in the biological application of this technique is how the freezing rate and concentration of cryoprotectant...
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Effect of Freezing Conditions on Distances and Their Distributions Derived from Double Electron Electron Resonance (DEER): A Study of Doubly-Spin-Labeled T4 Lysozyme
Effect of Freezing Conditions on Distances and Their Distributions Derived from Double Electron Electron Resonance (DEER): A Study of Doubly-Spin-Labeled T4 Lysozyme
Publication year: 2012
Source: Journal of Magnetic Resonance, Available online 24 January 2012</br>
Elka R.*Georgieva, Aritro S.*Roy, Vladimir M.*Grigoryants, Petr P.*Borbat, Keith A.*Earle, ...</br>
Pulsed dipolar ESR spectroscopy, DEER and DQC, require frozen samples. An important issue in the biological application of this technique is how the freezing rate and concentration of cryoprotectant could possibly affect the...
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[NMR paper] An NMR study of the origin of dioxygen-induced spin-lattice relaxation enhancement an
An NMR study of the origin of dioxygen-induced spin-lattice relaxation enhancement and chemical shift perturbation.
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J Magn Reson. 2004 Dec;171(2):225-32
Authors: Prosser RS, Luchette PA
Due to its depth-dependent solubility, oxygen exerts paramagnetic effects which become progressively greater toward the hydrophobic interior of micelles, and lipid bilayer membranes. This paramagnetic gradient, which is manifested...
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[NMR paper] Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and
Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and magnetization transfer in the presence of an off-resonance irradiation field.
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J Magn Reson B. 1994 May;104(1):11-25
Authors: Kuwata K, Brooks D, Yang H, Schleich T
The derivation of a generalized relaxation matrix equation for the off-resonance rotating-frame spin-lattice...
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[NMR paper] Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and
Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and magnetization transfer in the presence of an off-resonance irradiation field.
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J Magn Reson B. 1994 May;104(1):11-25
Authors: Kuwata K, Brooks D, Yang H, Schleich T
The derivation of a generalized relaxation matrix equation for the off-resonance rotating-frame spin-lattice...
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[NMR paper] A 31P-NMR spin-lattice relaxation and 31P[1H] nuclear Overhauser effect study of soni
A 31P-NMR spin-lattice relaxation and 31P nuclear Overhauser effect study of sonicated small unilamellar phosphatidylcholine vesicles.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles A 31P-NMR spin-lattice relaxation and 31P nuclear Overhauser effect study of sonicated small unilamellar phosphatidylcholine vesicles.
Biochim Biophys Acta. 1992 Feb 17;1104(1):137-46
Authors: Tauskela JS, Thompson M
The motional properties of the inner and outer monolayer headgroups of...
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[NMR paper] Off-resonance rotating frame spin-lattice NMR relaxation studies of phosphorus metabo
Off-resonance rotating frame spin-lattice NMR relaxation studies of phosphorus metabolite rotational diffusion in bovine lens homogenates.
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Biochemistry. 1990 Aug 21;29(33):7547-57
Authors: Caines GH, Schleich T, Morgan CF, Farnsworth PN
The rotational diffusion behavior of phosphorus metabolites present in calf lens cortical and nuclear homogenates was investigated by the NMR technique of...