Tutors : dr hab. Michał Bielejewski, prof. IFM PANdr hab. Joanna Kowalczuk , prof. IFM PAN Institute of Molecular Physics, Polish Academy of Sciences, Poznań, Poland
The word diffusion derives from the Latin word diffundere, which means "to spread out". In the most general case, diffusion is a phenomenon that refers to the net movement of an object driven by a gradient of some magnitude factor. The process has a stochastic nature, and its concept plays an important role in many areas of physics, chemistry, biology, sociology, economics, and finance, constituting a broad field for research. In natural sciences, diffusion is not limited to a given state of matter but can occur in solids, liquids, and gases. It conditions the life processes by determining the transport through membranes, cells eventually, the whole body. In chemical processes, it is often the central rule driving many reactions. In physics, it defines many transport processes for atoms, ions, or molecules. A distinguishing feature of diffusion is that it depends on particle random walk and results in mixing or mass transport without requiring directed bulk motion. The first description of the diffusion phenomena was given by Adolf Fick in 1855. Fick's laws can be used to solve for the diffusion coefficient, D. A diffusion process that obeys Fick's laws is called normal or Fickian diffusion. On the other hand, it is called anomalous diffusion or non-Fickian diffusion if the process does not follow these laws. This tutorial aims to give an overview of the wide range of applications of diffusion NMR and principles of NMR diffusometry methods that allow insight, for example, for accurate molecular size determination, in nanomedicine drug delivery, or separation of complex mixtures.
Tutor: dr Jacek Jenczyk NanoBioMedical Centre, Adam Mickiewicz University, Poznań, Poland
The aim of the workshop will be to introduce and explain the basics of chemical shift anisotropy and dipolar interations. I will try to visualize the tensor formalism present in the description of both and thus, in an intuitive way, show a direct relationship between the molecular orientation relative to the laboratory reference system and the evolution of the NMR spectrum. Furthermore, we will discuss the physical significance of the shielding tensor geometry and confront it with the distribution of electronic charge density around the nucleus. We will also try to understand the origin of D tensor geometry. Finally, I will try to explain what actually happens to tensors under magic angle spinning conditions and how MAS influences and modulates effective shielding and dipolar coupling.
D tensor under MAS conditions
carbon shielding tensor in ethylene molecule
Tutor: Prof. Danuta Kruk University of Warmia and Mazury,Olsztyn, Poland
Some time ago, the first relaxation equation was introduced - a remarkably simple model involving just two parameters: a dipolar relaxation constant and a correlation time. It described the spin-lattice relaxation rate as the sum of two Lorentzian functions and it was met with enthusiasm and became widely known as the Bloembergen – Purcell - Pound (BPP) formula. Then, relaxation processes in various molecular and ionic systems started to be investigated and the expression turned out to be insufficient. Several relaxation features were observed (some of them quite peculiar) and next, much more complex relaxation expression were needed – but where to get them from? Please do not treat this story literally. My intention is to say that to profit from the remarkable experimental opportunities, a parallel theoretical development is needed.The aim of this workshop is to explain the quantum-mechanical foundation of the Redfield relaxation theory. The theory is based on the second order perturbation approach and includes Hamiltonians, Wigner rotation matrices, transformation, Liouville representation, relaxation matrices and multi-quantum coherences. This is a robust framework which can be used for an arbitrary spin system as long as one can clearly define the main (time-independent) Hamiltonian and the perturbing (time-dependent) Hamiltonian. I will demonstrate how to derive the BPP formula following the formalism of the Redfield relaxation theory and I will explain the limitations of this expression. Then I will show why for systems including non-equivalent nuclei (such as 1H and 19F) one has to use different expressions and why in such cases the relaxation process is (in principle) bi-exponential. This is the right moment to point out that bi-exponentiality (non-exponentiality) of relaxation processes are not necessarily associated with dynamical heterogeneity – this effect can be entirely of quantum-mechanical origin. Once, the formalism becomes more familiar, I will show how to build the relaxation matrices for complex spin systems and extract from them relaxation rates describing specific spin coherences. I will use this opportunity to explain the quantum-mechanical foundation of Paramagnetic Relaxation Enhancement and Quadrupole Relaxation Enhancement.
Tutor: Dr Rafał Konefał NanoBioMedical CentreAdam Mickiewicz University, Poznań, Poland
Polymers are substances composed of polymer molecules (macromolecules) formed through the repetition of smaller subunits. Due to their diverse properties, both artificial and natural polymers are integral to everyday life. They find applications across a vast array of fields, including electronics, packaging, textiles, energy, and healthcare (e.g., drug delivery). This tutorial focuses on the practical implementation of Nuclear Magnetic Resonance (NMR) spectroscopy as a crucial tool in polymer chemistry. Emphasizing its specialized applications, the session is divided into areas such as structural determination, monomer sequence analysis in copolymers, end-group analysis, and polymer chain dynamics and interactions. Rather than concentrating on theoretical aspects, the tutorial provides actionable insights for researchers. Key topics include:1. Sample Preparation: highlighting experimental challenges such as preparation of sample solutions, selecting appropriate solvents, and determining experimental parameters.2. Structural Analysis: determining polymers structure as well as structural details like tacticity, copolymer composition, molecular weight and reaction kinetics.3. Polymer Dynamics Analysis: Utilizing NMR relaxation experiments, such as T1, T2, DOSY and nuclear Overhauser enhancement (NOE), to investigate polymer chain dynamics and interactions in solution. It is our wish, that the basics in NMR measurements presented in this workshop will be helpful and useful for NMR users as well as newcomers into the field of polymer research.
Tutor: Dr Anna Zawadzka-Kazimierczuk Biological and Chemical Research Centre,University of Warsaw, Poland
The workshop is a continuation of the lecture of the same title. The goal is to learn how to use 5D NMR spectra in practice. The students will get the following set of spectra [1,2] of an intrinsically disordered protein, alpha-synuclein:3D HNCO5D HN(CA)CONH5D (HACA)CON(CA)CONH5D (H)NCO(CAN)CONH5D HabCabCONH.We will work in the Sparky program.
Tutor: Prof. Pedro Jose Sebastiao Instituto Superior Técnico, CeFEMA University of Lisbon
fitteia.org has gain some popularity in recent years among different model/function fitting software alternatives available for the NMRD community [1-2]. It is a software application that requires the use of web browser to access the fitteia.org servers. Its user friendly graphical user interface is particularly suitable for model fitting to NMRD profiles taking advantage of its relaxation models library [3]. More recently, there has been an increasing demand of standalong implementations of the fitteia.org fitting engine to allow for either the automatic processing of data sets or for the embedding, or merging, of its fitting tools and libraries with other applications. The OneFit-Engine (OFE) is an attempt to provide users with a software package and installation tools that will increase enormously the possibilities offered by fitteia.org, including the development of alternative web interfaces to OFE engines [4,5]. In this tutorial the installation of OFE will be presented in detail together with a few examples of applications [4]. For a more immersive experience users should try to install in their computers the following software packages:MS Windows: 1- Virtual Box (https://www.virtualbox.org from Oracle) 2- PowerShell (https://learn.microsoft.com/en-us/powershell/) 3- https://gitforwindows.org 4- https://curl.se/windows/ Mac OS: 1) UTM https://mac.getutm.app (Virtual Box also works fine) References [1] "The art of model fitting to experimental results", P.J. Sebastião, Eur. J. Phys. 35, 15017 (2014)[2] "The art of fitting ordinary differential equations models to experimental results" P.J. Sebastiao et al. , Eur. J. Phys. 43, 035807 (2022) [3] http://NMRDpedia.org [4] https://github.com/fitteia/OneFit-Engine [5] http://onefite-t.vps.tecnico.ulisboa.pt:3000
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