Nuclear Spin Relaxation In Liquids Research Articles

K. Kamienska-Trela (Ed.): Nuclear Magnetic Resonance. Volume 40. Specialist Periodical Reports of the Royal Society of Chemistry

This volume is a compilation and summary of the nuclear magnetic resonance (NMR) spectroscopy literature from June 2009 to May 2010 and is the latest in a long line of similar volumes, the first being published in 1972. Selected aspects of NMR spectroscopy are chosen for each volume, because it would indeed be impossible to cover the whole of the NMR literature for even one year in a single volume. In this edition, the first chapter lists NMR books and reviews for the period in question, these alone providing 635 references. The next two chapters describe research into theoretical and physical aspects of nuclear shielding (the property giving rise to the chemical shift) including full tensor calculations and isotope shifts, followed by applications of nuclear shielding, covering comprehensively all of the various nuclides that give rise to NMR spectra. Similarly the next two chapters cover theoretical aspects of spin–spin couplings (by this is meant only the indirect or J-coupling, although there is a short section on residual dipolar couplings as seen in oriented samples), again covering a wide range of nuclear pairs and also anisotropy in the J tensor, followed by applications of spin–spin couplings for many pairs of nuclides, listing interactions over one, two, three and more bonds, plus through-space effects and couplings across hydrogen bonds. One section lists new pulse methods for obtaining J-coupling values. Next comes an excellent critical review chapter on nuclear spin relaxation in liquids and gases covering theory, experimental methods and selected applications. This is followed by a chapter on solid state NMR spectroscopy, describing new experimental methods, determination of NMR parameters for both spin one-half and quadrupolar nuclei, and applications ranging over organic and inorganic systems, amino acids, peptides and proteins, biomedical and pharmaceutical systems, coals, polymers, glasses, porous solids and surfaces. There are also subsequent chapters on applications of NMR spectroscopy to proteins and nucleic acids, carbohydrates, lipids and membranes, synthetic macromolecules, liquid crystals and micellar solutions and finally NMR in living systems, including new methodologies. The fields chosen are all very active, ranging over physical, organic, analytical and biological chemistry, with much research being undertaken across the world. The coverage of the literature has resulted in thousands of citations just in these selected fields, with several chapters providing over 400 references. Whilst the book provides a comprehensive compilation of the literature over the designated 12-month period (with one chapter covering 24 months from June 2008), in general there is not a great deal of critical review of the papers cited and of course by the time the book is published even the latest references are Bibliography

Nuclear Spin Relaxation in Liquids and Gases

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

Nuclear Spin Relaxation in Liquids and Gases

AbstractFor Abstract see ChemInform Abstract in Full Text.

Nuclear Spin Relaxation in Liquids and Gases

AbstractFor Abstract see ChemInform Abstract in Full Text.

Nuclear Spin Relaxation in Liquids and Gases

AbstractFor Abstract see ChemInform Abstract in Full Text.

Nuclear Spin Relaxation in Liquids and Gases

ChemInformVolume 33, Issue 43 p. 298-298 Reviews Nuclear Spin Relaxation in Liquids and Gases R. Ludwig, R. Ludwig Univ. Dortmund, D-44221 Dortmund, GermanySearch for more papers by this author R. Ludwig, R. Ludwig Univ. Dortmund, D-44221 Dortmund, GermanySearch for more papers by this author First published: 19 May 2010 https://doi.org/10.1002/chin.200243298AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume33, Issue43October 29, 2002Pages 298-298 RelatedInformation

Comment on "Intermolecular translational-rotational contribution to nuclear-spin relaxation in liquids"

A recent theoretical treatment of intermolecular nuclear-spin relaxation that incorporates the effect of molecular rotation @K. Lendi, Phys. Rev. A 45, 7906 ~1992!# is shown to be based on what appears to be a mistaken assignment of Euler angles. In particular, the conditional probability for reorientation of the intermolecular vector due to molecular rotation seems to be given incorrectly. Unsolvable integrals that are examined by Lendi are derived without considering the reflecting wall boundary conditions that are requisite for the problem of translational diffusion. @S1050-2947~96!09906-4#

Reply to "Comment on 'Intermolecular translational-rotational contribution to nuclear-spin relaxation in liquids' "

Reply to "Comment on 'Intermolecular translational-rotational contribution to nuclear-spin relaxation in liquids' "

Intermolecular translational-rotational contribution to nuclear-spin relaxation in liquids.

The intermolecular contribution to spin relaxation by translational-rotational diffusion dynamics in molecular liquids is calculated for arbitrary relative time scales of the two stochastic processes. The resulting relaxation times are functions of variables that are proportional to ratios between rotational and translational diffusion constants, in substantial generalization of earlier theoretical approaches. In the first part the general treatment for symmetric-top molecules is given with a reduction to quadratures and a simpler version for the spherical case

High-field nuclear spin relaxation in liquids and solids

The authors generalise the standard theory of nuclear spin relaxation to situations in which the Markovian approximation is not applicable. Expressions for generalised frequency-dependent spin relaxation functions are presented. They show that under high-field conditions the relaxation of longitudinal magnetisation is exponential independent of the particular time dependence of the correlation functions.

Nuclear spin relaxation in liquids due to interaction with paramagnetic ions having anisotropic g tensors

Analytical expressions are derived for spin-lattice and spin-spin relaxation times ( T 1M and T 2M) of a nucleus arising from magnetic interactions (dipolar and contact) with a paramagnetic ion which has an anisotropic g tensor. The relaxation rates depend on the orientation of the ion-nucleus vector in the principal-axis system of the g tensor. The deviations caused by this angular dependence with reference to the corresponding relaxation rates for an isotropic g tensor are numerically illustrated by considering a case typical for Co (II) complexes.

ChemInform Abstract: Nuclear Spin Relaxation in Liquids

ChemInformVolume 18, Issue 5 Reviews ChemInform Abstract: Nuclear Spin Relaxation in Liquids H. + WEINGAERTNER, H. + WEINGAERTNER Univ. Karlsruhe, D-7500 KarlsruheSearch for more papers by this author H. + WEINGAERTNER, H. + WEINGAERTNER Univ. Karlsruhe, D-7500 KarlsruheSearch for more papers by this author First published: February 3, 1987 https://doi.org/10.1002/chin.198705352Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume18, Issue5February 3, 1987 RelatedInformation

Dipolar nuclear spin relaxation in liquids and plane fluids undergoing chemical reactions

We describe the correlated translational and rotational relative brownian motions of two reacting groups of atoms, alternatively bound and free, by the normalized solutions of a set of coupled diffusion equations. Under equilibrium conditions we calculate the spectral densities j(ω) characteristic of the fluctuations of the intermolecular dipolar coupling between spins of these diffusing groups of atoms. When ωτ ≪ 1, where τ is the translational correlation time, the form of the spectral density j 2(ω) in three-dimensional liquids is j 2(0) - α3ω1/2. The coefficient α3 is independent of the molecular local order, of the diffusional rotation speed of the spin-carrying groups of atoms and of their association and dissociation rates. In plane fluids, when ωτ ≪ 1, the spectral density j (0)(ω) may be written as -a 2 ln (ωτ) where the dependence of a 2 on the average relative distribution of the interacting spins varies with the rate of the chemical reactions. In both three- and two-dimensional fluids spectral densities show an ω-3/2 or ω-2 behaviour for ωτ ≫ 1 according to the magnitude of the association rate of the reacting groups of atoms. In liquid glycerol we analyse the low- and high-frequency limits of the experimental proton relaxation rate 1/T 1 and 1/T 1ρ measured by Harmon, Harmon and Burnett, and Lenk. We also discuss the proton spin-lattice relaxation times measured by Kleinberg and Silbernagel in layered intercalation compounds TiS2-NH3 and TaS2-NH3.

Three-atom correlations in nuclear quadrupolar relaxation in liquids

Quadrupolar processes in diffusion-based nuclear spin relaxation in liquids are shown to be more strongly dependent on the three-atom distribution than dipolar processes. The quadrupolar relaxation may give information about the second-order term in an expansion of this distribution function.

Instrumentation for the Earth's Field NMR Technique

An instrument utilizing free precession in the earth's magnetic field has been developed for studying the field dependence of nuclear spin relaxation in liquids. Both 1H and 19F nuclei are accessible to measurement. The method requires that a current be switched on in the sample coil for a certain time, reduced quickly to some smaller value, and later reduced suddenly to zero. The resulting sample magnetization then precesses about the earth's magnetic field, inducing a voltage in the coil which is amplified and displayed on an oscilloscope screen. The sample coil, current switching circuit, signal detection circuit, and timing circuits are described. The instrument is capable of measuring spin-lattice relaxation times (T1) of 30 msec and up in fields ranging from 2 to 500 G; the range of measurable spin-spin relaxation times (T2) is 10 msec-1 sec in the earth's field of 0.54 G. The signal-to-noise ratio for a 450 ml water sample is greater than 700:1 at a bandwidth of 20 Hz. Estimated precision of the relaxation time measurements is ±3%.

Nuclear magnetic resonance in the study of liquids

Mechanisms of nuclear spin relaxation in liquids are listed and discussed. It is pointed out that measurements of spin relaxation times (and also dielectric relaxation times) give information about different aspects of the process of molecular rotation and re-orientation in liquids. Comparative studies of different mechanisms should lead to a more detailed understanding of these movements.

Nuclear Spin Relaxation in Liquids. Spheroidal Molecules

Nuclear spin—lattice relaxation times have been measured as a function of temperature for a number of liquid hydrocarbons. These data, together with other available measurements on rigid, spheroidal molecules, are compared with the Bloembergen, Purcell, and Pound (B.P.P.) theory of spin—lattice relaxation in liquids, and it is shown that the B.P.P. calculation of the rotational contribution to the relaxation time gives a value which are much shorter than the total experimental relaxation times. It is then assumed that the time dependence of the rotational angular autocorrelation functions of these molecules is dominated by dynamical coherence, rather than by frictional forces as assumed in the B.P.P. theory. If one calculates the net spin—lattice relaxation time T1 by summing the translational contribution calculated from the B.P.P. theory and the rotational contribution calculated from an approximate autocorrelation function valid for small but nonzero friction constants, one obtains values for T1 which are in quantitative agreement with the data for nonpolar, spheroidal molecules. Furthermore, when the two calculations are compared with the data for polar spheroidal molecules, it is seen that frictional forces are the predominant factor in the rotational motion of these systems, but the values obtained for the rotational friction constant from the Stokes—Einstein equation are in error by a considerable amount.