NMR Research Unit

Laplace NMR (LNMR), comprising diffusion and relaxation NMR experiments, provides detailed information on the dynamics and chemical resolution of molecular systems, which is complementary to NMR spectra. Based on spatial encoding of multidimensional data, we develop a broad range of single-scan LNMR experiments, constituting a new class of NMR experiments called ultrafast multidimensional LNMR. The method shortens the experiment time by one to three orders of magnitude as compared to the conventional method, offering unprecedented opportunity to study fast processes in real time.

We also apply these method in collaboration with other researcher groups, e.g., in characterization of zero-carbon cement materials, metabolic processes in cancer cells and in climate-related studies of aerosols.

An emerging paradigm in theoretical molecular and materials sciences is computational spectroscopy, which in the case of magnetic resonance spectroscopy means computing directly the primary experimental observables, the time-dependent magnetization or the resulting spectrum. This is to be compared with the traditional way in which comparison with experiment is done at the level of NMR spectral parameters or relaxation times, which themselves result from applying theoretical models to the measurement data. We realise computational spectroscopy by multiscale modelling of atomic dynamics within the material; electronic interactions of the spins at each set of atomic positions and the resulting time dependence of the nuclear and electron spin density matrices. This procedure enables detailed, microscopic interpretation and development of relaxation and polarisation transfer processes of relevance to modern magnetic resonance.

We develop advanced experimental and computational NMR methods and apply them for materials research in gas, liquid, and solid states. Computational modeling involves electronic structure calculations of NMR parameters in molecules as well as in cluster and periodic models of solid-state materials that are combined with Monte Carlo (MC) and molecular dynamics (MD) simulations in order to deal with the thermal and environmental effects. Due to presence of heavy elements in the materials, relativistic methods are often utilized in electronic structure calculations. The materials include, for example ionic liquids, liquid crystals, porous media, wood, lignins, nanocellulose, cement, shale, geopolymers and soil organic matter. In addition, we study different dia- and paramagnetic materials, such as rare earth element (REE) phosphates, supramolecular, clathrate, cryptophane, and fullerene cages, graphenes and carbon nanotubes, as well as heavy elements (e.g. REEs, Pt, Hg, Bi) containing materials like single-molecule magnets with spintronics applications.

Magnetic resonance methods, NMR spectroscopy and imaging, offer versatile tools for molecular level analysis, enabling advanced characterization of catalytic processes. Often, their low sensitivity, dictated by low signal amplitudes, sets significant limitations. We develop catalytic processes that improve NMR sensitivity by orders of magnitude with spin hyperpolarization based on the use of parahydrogen, a spin modification of molecular hydrogen (H2), as a source of hyperpolarized molecules produced catalytically. We use this approach to perform mechanistic characterization of homogenous and heterogeneous catalysts and reaction imaging. Based on emerging advancements in metal-free catalysis, we develop metal-free activators for parahydrogen to create hypersensitive non-toxic sensors for biomolecular studies.

Nuclear magneto-optic spectroscopy (NMOS) is a group of new methods for optical detection of nuclear magnetization. In standard NMR spectroscopy the signal is registered as a voltage induced by the precessing nuclear magnetization. In contrast, the principle of NMOS is measuring how a light beam passing through the sample is affected by these small local magnetic fields produced by the nuclei. NMOS is a whole group of methods, encompassing several optical effects, such as circular birefringence, circular dichorism or linear birefringence. We are developing new theoretical models and experimental setups for observation and deeper understanding of these new effects.