Geoffrey Bodenhausen

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By monitoring the effect of deuterium decoupling on the decay of transverse N-15 magnetization in D-N-15 spin pairs during multiple-refocusing echo sequences, we have determined fast D-D exchange rates k(D) and compared them with fast H-H exchange rates k( ...

A simple variation of double-quantum spectroscopy is described where the transfer of double- into single-quantum coherence is carried out by means of 2 pulses with small flip angles via eigenstate populations and zero-quantum coherences. For systems with 4 or more spins, the sensitivity of the new expt. is comparable to or better than that of conventional double-quantum spectroscopy with a single 90 Deg monitoring pulse. The resulting spectra feature simple 2D multiplets that are composed of juxtapositions

A novel class of NMR expts., based on the systematic variation of 3 time variables, permits both the identification of exchange networks and the direct measurement of the corresponding rate consts. in soln. Linear combinations of cross sections taken from 2 dimensional spectra allow a straightforward anal. of nonexponential recovery behavior by identifying normal modes. The line widths of the resulting Lorentzian line shapes provide a direct measure of the rate consts. of various dynamic processes, such as

Several methods are presented for the selective determination of spin-lattice and spin-spin relaxation rates of backbone protons in labeled proteins. The relaxation rates of amide protons in (15)N labeled proteins can be measured by using two-way selective cross-polarization (SCP). The measurement of H(alpha) relaxation rates can be achieved by combining this method with homonuclear Hartmann-Hahn transfer using doubly selective irradiation. Various schemes for selective or nonselective inversion of the long

Ligands that have an affinity for protein targets can be screened very effectively by exploiting favorable properties of long-lived states (LLS) in NMR spectroscopy. In this work, we describe the use of LLS for competitive binding experiments to measure ac ...

PROBLEM TO BE SOLVED: To provide a method for extending longitudinal relaxation time and transverse relaxation time in nuclear magnetic resonance (NMR), while removing free radicals from hyperpolarized solution. SOLUTION: A method for preparing samples for ...

Methods and spectrometers for carrying out ion-cyclotron-resonance spectrometry are described in which a pulse sequence is employed which is described by P1-t1-P2-Tm-P3-t2, (P1, P2, and P3 are radio-frequency pulses, with P1 and P2 having the same frequency; t1 and Tm are time intervals between the pulses; and t2 is the observation time following the last pulse); the sequence is repeated several times while varying t1 to obtain a plurality of induction signals during t2, from which a 2-dimensional spectrum

Pulsed Field Gradients (PFGs) have become ubiquitous tools not only for Magnetic Resonance Imaging (MRI), but also for NMR experiments designed to study translational diffusion, for spatial encoding in ultra-fast spectroscopy, for the selection of desirabl ...

A half-century quest for improving resolution in Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI) has enabled the study of molecular structures, biological interactions, and fine details of anatomy. This progress largely relied on the ...

An anal. was made of the effects of nonexponential transverse relaxation during the free precession periods of 2-dimensional NMR expts. The presence of cross-correlation between various interactions that cause relaxation, such as chem. shift anisotropy and dipole-dipole interactions, may lead to the creation of spin-ordered states that make coherence transfer processes possible in spite of the absence of scalar, dipolar or quadrupolar splittings. The principal example discussed in the context of 2-dimension

The interface between solid surfaces and cavities filled with gaseous 131Xe can be probed by multiple-quantum filtered NMR. Physisorbed 131Xe is usually not directly observable by NMR spectroscopy, but information can be transferred into the gas phase through desorption. The exchange process may lead to higher-rank order of the nuclear spins in gaseous Xe which can be detected by multiple-quantum filtered NMR. [on SciFinder (R)]

The authors describe a two-dimensional high-resoln. solid-state NMR methodol. for correlating the dynamics of mol. rearrangements around the crit. points of equil. phase transitions in mol. solids. It combines the techniques of temp.-jump and two-dimensional (2D) NMR spectroscopy. The two spectral dimensions are the isotropic chem. shifts at different sample temps. The technique is illustrated by elucidating the dynamic rearrangement of the C4O4 units of squaric acid (H2C4O4) in relation to the mechanism of

In this paper some effects of dynamical coupling between two interaction-carrying vectors on the internal auto- and cross-correlation functions are investigated in the limit of small amplitude motions. A linearized Langevin approach allows the derivation of explicit expressions for these correlation functions and for the corresponding order parameters. [on SciFinder (R)]

Nuclear magnetic resonance spectroscopy (NMR) can provide a great deal of information about structure and dynamics of biomolecules. The quality of an NMR structure strongly depends on the number of experimental observables and on their accurate conversion ...

The transverse relaxation rates R (2) = 1/T (2) of protons can be determined by spin-echo sequences with multiple refocusing pulses using moderate radio-frequency field strengths and properly chosen inter-pulse delays so as to suppress echo modulations due to homonuclear scalar couplings. Combination with 2D heteronuclear correlation spectroscopy (HSQC) allows one to measure R (2) of arbitrary protons attached to nitrogen-15 or carbon-13 nuclei. Decays of six amide protons in the protein Ubiquitin that is n

New radio-frequency pulse envelopes are presented for selective inversion and in-phase excitation in NMR. The envelope functions consist of superpositions of three or four time-shifted Gaussians with optimized widths and peak amplitudes. The offset dependence closely approaches ideal rectangular functions, as verified by simulation and expt. [on SciFinder (R)]

The impact of Nuclear Magnetic Resonance (NMR) on studies of large macromolecular complexes hinges on improvements in sensitivity and resolution. Dynamic nuclear polarization (DNP) in the solid state can offer improved sensitivity, provided sample preparat ...

Chem. shift anisotropy (CSA) tensor parameters have been detd. for the protonated carbons of the purine bases in an RNA kissing complex in soln. by extending the model-independent approach [Fushman, D., Cowburn, D. (1998) J. Am. Chem. Soc. 120, 7109-7110]. ...

Two-dimensional NMR techniques which sep. the chem. shift and heteronuclear dipolar interactions were applied to samples spinning at the magic angle. Because of the inhomogeneous nature of the 2 interactions, rotational echoes were obsd. in the time domain of each dimension. The corresponding Fourier transforms yield rotational sideband spectra which provide information on the principal values and relative orientations of the shift and dipolar tensors, and from the latter, internuclear distances may be calc

Spurious responses, known as phantom and ghost responses, in NMR 2-dimensional J spectroscopy, can be removed by a 4-step sequence where the phase of the C refocusing pulse is cycled through O, 90, 180, 270 Deg while the receiver ref. phase is alternated. This phase-cycling sequence was applied to the 2-dimensional J spectrum of 13C in MeOH obtained by the proton flip technique; both the phantom and ghost multiplets were canceled. [on SciFinder (R)]

Geoffrey Bodenhausen

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Kinetic isotope effects for fast deuterium and proton exchange rates

Double-quantum z-filtered NMR spectra and automated analysis by pattern recognition

Direct determination of rate constants of slow dynamic processes by two-dimensional \"accordion\" spectroscopy in nuclear magnetic resonance

Measurement of relaxation rates of N(H) and H(alpha) backbone protons in proteins with tailored initial conditions

Exploring Weak Ligand-Protein Interactions by Long-Lived NMR States: Improved Contrast in Fragment-Based Drug Screening

Method for nmr spectrometry or mri measurement using dissolution dynamic nuclear polarization (dnp) with scavenging of free radicals

Method for recording ion-cyclotron-resonance mass spectra and mass spectrometer designed for carrying out the method

Single or triple gradients?

Ultrahigh-Resolution Magnetic Resonance in Inhomogeneous Magnetic Fields: Two-Dimensional Long-Lived-Coherence Correlation Spectroscopy

Relaxation-allowed cross-peaks in two-dimensional NMR correlation spectroscopy

Multiple-Quantum Filtered Xenon-131 NMR as a Surface Probe

Temperature-Jump 2D NMR Spectroscopy in Crystalline Solids: A Technique for Correlating Molecular Reorientation across the Phase Boundaries of an Order-Disorder Lattice

A simple model for NMR relaxation in the presence of internal motions with dynamical coupling

Nuclear overhauser spectroscopy of chiral CHD methylene groups

Transverse Relaxation of Scalar Coupled Protons in Magnetic Resonance of Non-Deuterated Proteins

Gaussian pulse cascades: new analytical functions for rectangular selective inversion and in-phase excitation in NMR

Solid-state NMR enhanced by dynamic nuclear polarization as a novel tool for ribosome structural biology

Determination of 13C CSA Tensors: Extension of the Model-independent Approach to an RNA Kissing Complex Undergoing Anisotropic Rotational Diffusion in Solution

Two-dimensional rotational spin-echo nuclear magnetic resonance in solids: correlation of chemical shift and dipolar interactions

Suppression of artifacts in two-dimensional J spectroscopy