Abstract: A method of projection spectroscopy for N-dimensional NMR experiments with the following steps. Data recording through; a) selection of N-dimensional NMR experiments out of a group of N-dimensional experiments, selection of the dimensionalities (Di) of the projections and unconstrained selection of j sets of projection angles, with j?2; b) recording of discrete sets of j projections from the N-dimensional NMR experiments at the selected projection angles; c) peak picking and creating a peak list for each of the j projection spectra is characterized by d) automated identification of peaks in the projection spectra that arise from the same resonance in the N-dimensional spectrum (N?3) using vector algebra to exploit geometrical properties of projections in the N-dimensional space, and computation of a N-dimensional peak list using vector algebra to exploit geometrical properties of projections in the N-dimensional space.

Abstract: A method of projection spectroscopy for N-dimensional NMR experiments with the following steps. Data recording comprising: a) selection of N-dimensional NMR experiments out of a group of N-dimensional experiments, selection of the dimensionalities (Di) of the projections and unconstrained selection of j sets of projection angles, with j?2; b) recording of discrete sets of j projections from the N-dimensional NMR experiments at the selected projection angles; c) peak picking and creating a peak list for each of the j projection spectra is characterized by d) automated identification of peaks in the projection spectra that arise from the same resonance in the N-dimensional spectrum (N?3) using vector algebra to exploit geometrical properties of projections in the N-dimensional space, and computation of a N-dimensional peak list using vector algebra to exploit geometrical properties of projections in the N-dimensional space.

Abstract: A method for performing polarization transfer in NMR experiments with coupled spin ½ nuclei I and S being irradiated by a sequence of rf pulses comprising a first 90° pulse exciting the spins of the nuclei I and after a delay time a further 90° pulse exciting the spins of the nuclei S is characterized in that there is no inversion pulse acting on the spins of the nuclei S during a time period T between the first 90° pulse exciting the spins of the nuclei I and either the further 90° pulse exciting the spins of the nuclei S or a second 90° pulse acting on the spins of the nuclei I, and that the length of the time period T is chosen such that d/dT[{square root over (sinh+L (RCT+L )2+L +sin(&pgr;JIST+L )2+L )} exp(−RIT)] is minimized, where RC is the transverse cross-correlation-relaxation rate of nuclei I, RI is the total transverse relaxation rate of nuclei I and JIS is the scalar coupling constant between nuclei I and S.

Abstract: A method for obtaining a nuclear magnetic resonance (NMR) correlation spectrum of heteronuclear spin systems, in particular comprising large molecules, especially biological macromolecules in solution, the spin system being subjected to a homogeneous magnetic field B.sub.0, being irradiated by a sequence of radio frequency (rf) pulses, is characterized in that the spin system comprises at least two kinds of spin 1/2 nuclei I and S being coupled to each other, whereby the sequence of rf pulses is chosen such that line broadening in the observed spectrum due to transverse relaxation (T.sub.2) is significantly reduced because of cross correlation between dipole--dipole (DD) coupling of the spins and chemical shift anisotropy (CSA), giving rise to different relaxation rates of the individual multiplet components of the spin system and chosen such that the relaxation effects of the two different mechanisms cancel each other out to a large degree. Thus, even very large biological macromolecules can be measured.