Geoffrey Bodenhausen

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Cross-correlation between pairs of dipole-dipole interactions may lead to a partial conversion of longitudinal Zeeman magnetization into longitudinal three-spin order, which can be obsd. selectively by using a triple-quantum filter in conjunction with two-dimensional exchange expts. The resulting TQF-NOESY method (triple-quantum filtered nuclear Overhauser effect spectroscopy) provides information about angles subtended by internuclear vectors. [on SciFinder (R)]

The paramagnetic complex bis(oxazolinylphenyl)amine-Fe(III)Cl-2 is investigated by means of solid-state proton NMR at 18.8 T (800 MHz) using magic-angle spinning at 65 kHz. Spin echoes that are excited and refocused by combs of rotor-synchronized pulses in ...

In high-resoln. NMR, a network of scalar-coupled spins can be broken down into fragments which encode information about the chem. shifts and couplings that are relevant to a cross-peak multiplet in a two-dimensional correlation ("COSY") expt. Novel selective two-dimensional NMR correlation methods ("soft-COSY") are described which allow one to identify fragments on the basis of their topol. These new expts. allow one to "zoom in" on complicated cross-peak multiplets and include "passive spin filters\

The polarisation of abundant protons, rather than dilute nuclei with low gyromagnetic ratios, can be enhanced in less than 10 min using dissolution DNP and converted into a long-lived state delocalised over an ensemble of three coupled protons. The process is more straightforward than the hyperpolarisation of heteronuclei followed by magnetisation transfer to protons.

A significantly increased resolution in the proton-coupled 13C NMR spectrum of MeI was achieved by 2-dimensional J spectroscopy. [on SciFinder (R)]

We propose a new scheme for heteronuclear decoupling designed for fast magic-angle spinning (MAS), dubbed phase-inverted supercycled sequence for attenuation of rotary resonance (PISSARRO). Its efficiency compares favourably with CW, TPPM, SPINAL and XiX d ...

NMR pulse expts. are described in terms of pathways through various orders of coherence. A general procedure is indicated for the systematic design of phase cycles that select desirable coherence-transfer pathways. [on SciFinder (R)]

Modified Jeener-Broekaert (1967) expts. are proposed for use in NMR spectroscopy of spins S = 1 nuclei in anisotropic phases. The new pulse sequences provide efficient creation of quadrupolar order over a wide range of values of the quadrupolar splitting. The new sequences can be used even under nonideal exptl. conditions. [on SciFinder (R)]

A simple design for a computer-controlled digital phase shifter is described. The device provides 24 different phases in increments of 15 Deg, though arbitrary increments can be obtained using the same basic approach. [on SciFinder (R)]

The magnetic shielding tensors of protons of water in barium chlorate monohydrate are investigated at room temperature by means of solid-state NMR spectroscopy, both for static powders and under magic-angle spinning conditions, using one- and two-dimension ...

A method is proposed for the sepn. of overlapping multiplets or substructure within multiplets in two-dimensional spectra. The issue of the recognition and measurement of homonuclear couplings in arbitrary mols. was discussed. The overlapping cross-peak multiplets from a soft-COSY spectra for trans- and cis-2-phenylcyclopropanecarboxylic acid Et ester was given as an example. [on SciFinder (R)]

The variable-speed magic-angle sample spinning (VSMAS) technique was extended to two-dimensional spectroscopy in solids yielding two-dimensional spectra free of spinning sidebands. [on SciFinder (R)]

Self-convolution and symmetry mapping were used to analyze proton multiplets in two-dimensional NMR spectra of the triterpene, obtusifolione (I). [on SciFinder (R)]

Hyperpolarization by Dissolution Dynamic Nuclear Polarization is usually achieved by monochromatic microwave irradiation of the ESR spectrum of free radicals embedded in glasses at 1.2 K and 3.35 T. Hovav et al. (2014) have recently shown that by using fre ...

Major breakthroughs have recently been reported that can help overcome two inherent drawbacks of NMR: the lack of sensitivity and the limited memory of longitudinal magnetization. Dynamic nuclear polarization (DNP) couples nuclear spins to the large reserv ...

Method for detg. the coupling const. between two spins using a suitably chosen pair of selective expts., soft-COSY on the one hand and pure in-pause correlation spectroscopy (PICST) on the other, is presented. In weakly coupled system, soft-COSY yields cross-peak multiplets with structures that are analogous to what can be obtained with small-flip-angle COSY or E.COSY. [on SciFinder (R)]

The envelopes of spin-echo amplitudes obtained with trains of multiple refocusing pulses are normally modulated by homonuclear scalar couplings. Echo modulations make it difficult to determine transverse relaxation rate constants R2. Provided that the puls ...

Geoffrey Bodenhausen

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Evidence for dipolar cross-correlation from triple-quantum-filtered two-dimensional exchange NMR spectroscopy

Solid-state proton NMR of paramagnetic metal complexes: DANTE spin echoes for selective excitation in inhomogeneously broadened lines

Selective two-dimensional NMR experiments for topological filtration of fragments of coupling networks

Proton hyperpolarisation preserved in long-lived states

Two-dimensional J spectroscopy: Proton-coupled carbon-13 NMR

Efficient heteronuclear decoupling by quenching rotary resonance in solid-state NMR

Selection of coherence-transfer pathways in NMR pulse experiments

Broadband excitation of quadrupolar order by modified Jeener-Broekaert sequences

A simple digital phase-shifter for multiple-quantum NMR

Solid-state NMR measurements and DFT calculations of the magnetic shielding tensors of protons of water trapped in barium chlorate monohydrate

Separation of overlapping multiplets and contraction of substructures within multiplets using symmetry properties

Suppression of sidebands in two-dimensional exchange and MQMAS spectroscopies in solids by variable-speed magic-angle sample spinning

Reflections of pathways: A short perspective on ‘Selection of coherence transfer pathways in NMR pulse experiments’

Similarities between self-convolution and symmetry mapping of multiplets in two-dimensional NMR spectra

Microwave frequency modulation to enhance Dissolution Dynamic Nuclear Polarization Dedicated to To Martial Rey, as a token of appreciation

Networks of Coupled Rotators: Relationship between Structures and Internal Dynamics in Metal-Binding Proteins. Applications to apo- and holo-Calbindin

Nitrogen-14 NMR Spectroscopy using Residual Dipolar Splittings in Solids

Long-lived states to sustain hyperpolarized magnetization

Determination of active scalar coupling constants by two-dimensional convolution of complementary cross-peak multiplets

Determination of transverse relaxation rates of individual spins while quenching echo modulations due to homonuclear scalar couplings