https://mr.copernicus.org/articles/ Combined list of the recent articles of the journal Magnetic Resonance and the recent discussion forum Magnetic Resonance Discussions en https://doi.org/10.5194/mr-2026-10 Floquet Theory and Average Hamiltonian Theory Revisited: Equivalence, Convergence and Applications to NMR Antonia Joëlle Bock, Matthias Ernst, and Götz Silvester Uhrig Magn. Reson. Discuss., https://doi.org/10.5194/mr-2026-10,2026 Preprint under review for MR (discussion: open, 0 comments) The analysis of magic-angle spinning nuclear magnetic resonance experiments often includes determining a constant effective replacement for a periodic time-dependent Hamiltonian. We provide a clarifying overview over the two most used approaches, covering their mathematical origin, context, and relationship to each other, as well as their practical use for nuclear magnetic resonance applications. We recommend Floquet theory due to its numerical robustness, efficiency and accuracy. Fri, 11 Sep 2026 22:23:44 +0200 https://doi.org/10.5194/mr-7-113-2026 Optimally controlled nuclear magnetic resonance (NMR) in electrochemistry: Larmor versus nutation frequency selective spin excitation for locally selective NMR experiments Johannes F. Kochs, Armin J. Römer, Michael Schatz, Matthias Streun, Sven Jovanovic, Rüdiger-A. Eichel, Simone S. Köcher, and Josef Granwehr Magn. Reson., 7, 113–123, https://doi.org/10.5194/mr-7-113-2026, 2026 We demonstrate the potential of designing magnetic resonance spectroscopy experiments for investigating electrochemically relevant setups. Up until now, such nuclear magnetic resonance measurements were heavily obstructed by the fact that conductive components interact with magnetic fields. In a new approach, we show that this interaction can be deliberately utilized to achieve a spatially selective measurement of electrochemical environments. Fri, 17 Jul 2026 22:23:44 +0200 https://doi.org/10.5194/mr-2026-9 Line-Narrowing by Polychromatic Selective Spin-Locking in NMR Coline Wiame, Hadi Loutfi, Kirill Sheberstov, and Geoffrey Bodenhausen Magn. Reson. Discuss., https://doi.org/10.5194/mr-2026-9,2026 Revised manuscript accepted for MR (discussion: closed, 6 comments) Selective Spin-Locking (SSL) of the magnetization vectors of selected singlets or multiplets in high-resolution Nuclear Magnetic Resonance (NMR) spectra by mono- or polychromatic selective radio-frequency (RF) irradiation can reduce the linewidths to the limit given by homogeneous T1ρ relaxation in the rotating frame. Mon, 06 Jul 2026 22:23:44 +0200 https://doi.org/10.5194/mr-7-99-2026 Segmented-overlap Fourier filtering and averaging (SOFFA) approach to improve concentration sensitivity of magnetic resonance spectra Jason W. Sidabras Magn. Reson., 7, 99–112, https://doi.org/10.5194/mr-7-99-2026, 2026 To measure very weak magnetic resonance signals without new hardware, we changed how data are collected. Rather than one long sweep, we recorded many short, overlapping pieces, cleaned each piece, and then merged them. On standard instruments and with equal measuring times, this increased usable signal compared with background by about 5 to 10 times across three test samples, helping reveal details that long averaging can hide. Thu, 02 Jul 2026 22:23:44 +0200 https://doi.org/10.5194/mr-7-89-2026 Dual bilinear rotations Yannik T. Woordes and Burkhard Luy Magn. Reson., 7, 89–98, https://doi.org/10.5194/mr-7-89-2026, 2026 Dual bilinear rotations are introduced, which lead to well-defined rotations for both heteronuclear spins I and S that depend on the presence or absence of a (large) coupling between them. These are therefore an extension of conventional bilinear rotations, which cause such a spin-system-dependent rotation only for the spin I. A general derivation of the approach is given, and a quadruple-J-resolved type experiment is introduced for demonstration. Wed, 24 Jun 2026 22:23:44 +0200 https://doi.org/10.5194/mr-7-81-2026 Excitation of delocalized long-lived states of aliphatic protons at low and high magnetic fields Sebastiaan Van Dyck, Coline Wiame, Kirill F. Sheberstov, and Geoffrey Bodenhausen Magn. Reson., 7, 81–88, https://doi.org/10.5194/mr-7-81-2026, 2026 It is shown that proton long-lived states can be observed on benchtop nuclear magnetic resonance spectrometers in molecules containing short aliphatic chains. The effects of strong coupling between methylene groups can be mitigated by optimizing the amplitude and duration of the excitation pulse. Mon, 22 Jun 2026 22:23:44 +0200 https://doi.org/10.5194/mr-2026-8 Comparing Fourier Transform and Direct Wave Fitting in NMR FID Data Analysis Jixin Chen Magn. Reson. Discuss., https://doi.org/10.5194/mr-2026-8,2026 Revised manuscript accepted for MR (discussion: closed, 5 comments) This study compares different ways to simulate NMR raw data and analyze such data. The results show that direct signal fitting can recover useful information from very short or weak signals where traditional methods struggle, helping improve future artificial intelligence tools for chemical analysis. Mon, 01 Jun 2026 22:23:44 +0200 https://doi.org/10.5194/mr-7-53-2026 Scalable modeling of multi-spin ensembles in SABRE hyperpolarization: a symmetry-based framework for zero and ultralow fields Danil Markelov, Alexander Snadin, Alexey Kiryutin, Danila Barskiy, and Alexandra Yurkovskaya Magn. Reson., 7, 53–79, https://doi.org/10.5194/mr-7-53-2026, 2026 We present a framework to simulate nuclear magnetic resonance (NMR) signal enhancement experiments using parahydrogen at ultralow magnetic fields. Our approach captures the full quantum evolution of the system while reducing computational complexity for multi-spin systems through symmetry-based dimensionality reduction. This enables efficient prediction of optimal polarization transfer fields and simulation of the resulting ultralow-field NMR spectra. Thu, 21 May 2026 22:23:44 +0200 https://doi.org/10.5194/mr-7-39-2026 An open-access WebApp for inverse Laplace transform analysis of time-domain nuclear magnetic resonance signals Tiago B. Moraes, Gustavo V. Von Atzingen, Larissa P. Mazzero, William S. Mendes, Marina B. Zacharias, and Marcelo C. B. Cardinali Magn. Reson., 7, 39–51, https://doi.org/10.5194/mr-7-39-2026, 2026 We developed a free online tool that helps researchers and students analyze nuclear magnetic resonance signals and extract meaningful information about materials such as foods, plants, and soils. The platform simplifies complex data processing and removes the need for specialized software. Tests with simulated and real data show reliable results, making advanced analysis more accessible for science and education. Thu, 23 Apr 2026 22:23:44 +0200 https://doi.org/10.5194/mr-7-29-2026 Accelerated 19F biomolecular magic-angle spinning NMR with paramagnetic dopants Lea M. Becker, Giorgia Toscano, Anna Kapitonova, Rajkumar Singh, Undina Guillerm, Roman J. Lichtenecker, and Paul Schanda Magn. Reson., 7, 29–37, https://doi.org/10.5194/mr-7-29-2026, 2026 Magic-angle-spinning nuclear magnetic resonance (NMR) is ideal for studying protein structure and dynamics. Introducing fluorine atoms offers advantages due to the NMR properties of 19F and the absence of natural fluorine. However, the slow spin polarisation recovery of 19F causes long recycle delays between scans. We demonstrate that adding paramagnetic co-solutes to solid protein samples largely accelerates these experiments, and we identify optimal conditions for this approach. Thu, 16 Apr 2026 22:23:44 +0200 https://doi.org/10.5194/mr-7-21-2026 Bimodal Q-band probehead with improved signal-to-noise ratio in pulse electron paramagnetic resonance Vasyl Denysenkov, Alexey Fedotov, Burkhard Endeward, and Thomas F. Prisner Magn. Reson., 7, 21–28, https://doi.org/10.5194/mr-7-21-2026, 2026 The developed probe head, which is a combination of the bimodal resonator operating in transmission mode and the low-noise amplifier, led to at least a 2-fold improvement in the sensitivity of the electron paramagnetic resonance spectrometer independent of sample temperature. The probe head is compatible with commercial Bruker spectrometers without their modification. Fri, 20 Mar 2026 22:23:44 +0100 https://doi.org/10.5194/mr-7-15-2026 The origin of mirror symmetry in high-resolution nuclear magnetic resonance spectra Dmitry A. Cheshkov and Dmitry O. Sinitsyn Magn. Reson., 7, 15–20, https://doi.org/10.5194/mr-7-15-2026, 2026 This research reveals the hidden rules that connect the perfect mirror-image shape of a high-resolution nuclear magnetic resonance spectrum to the properties of a molecule's nuclear spin system. We found that this symmetry occurs only when specific, balanced conditions are met within the spin system. Testing these rules on various theoretical models confirmed their universal nature, providing a new framework for interpreting molecular symmetry from spectral patterns. Wed, 11 Mar 2026 22:23:44 +0100 https://doi.org/10.5194/mr-7-1-2026 Robust bilinear rotations II Yannik T. Woordes and Burkhard Luy Magn. Reson., 7, 1–14, https://doi.org/10.5194/mr-7-1-2026, 2026 Bilinear rotations like BIRD, TANGO, BANGO, and BIG-BIRD are essential building blocks in modern nuclear magnetic resonance (NMR) spectroscopy that allow the rotation of an isolated spin without couplings (i.e., bilinear interactions) in one way, while rotating spins with a matched coupling in another way. Two ways for constructing particularly robust bilinear rotations (compensated for couplings, offsets, and B1 inhomogeneities, or COB/COB3) are provided and demonstrated in both theory and experiment. Thu, 05 Feb 2026 22:23:44 +0100 https://doi.org/10.5194/mr-2025-17 Pulsed Electron Paramagnetic Resonance on two Cu(II)-Cage Compounds With Six, Respectively Eight Copper Ions Leonardo Passerini, Eduard Bobylev, Felix J. de Zwart, Henrik Hintz, Adelheid Godt, Bas de Bruin, Joost Reek, and Martina Huber Magn. Reson. Discuss., https://doi.org/10.5194/mr-2025-17,2025 Revised manuscript not accepted (discussion: closed, 4 comments) We describe electron paramagnetic resonance (EPR) based distance measurements between six, respectively eight copper(II)-ions that occupy octahedral or cubic positions in self-assembled nano-meter-sized spherical cages. These cages, which are reminiscent of soccer balls, are made up of inorganic ligands and Pd-ions. Their geometric shape is aesthetically pleasing, and to show that the double electron electron resonance technique works for more than two copper-ions is the novelty of this study. Wed, 31 Dec 2025 22:23:44 +0100 https://doi.org/10.5194/mr-6-317-2025 Static-gradient NMR imaging for depth-resolved molecular diffusion in amorphous regions in semicrystalline poly(tetrafluoroethylene) film Natsuki Kawabata, Naoki Asakawa, and Teruo Kanki Magn. Reson., 6, 317–329, https://doi.org/10.5194/mr-6-317-2025, 2025 We developed a new, low-cost nuclear magnetic resonance imaging method to visualize how molecules move inside a solid polymer film. By examining different depths of a polytetrafluoroethylene film, we discovered that molecular motion is strongly limited near the supporting surface but more active at the air side. This finding helps explain how local environments affect the flexibility of polymer materials. Mon, 15 Dec 2025 22:23:44 +0100 https://doi.org/10.5194/mr-6-281-2025 Optimized shaped pulses for a 2D single-frequency technique for refocusing (SIFTER) Paul A. S. Trenkler, Burkhard Endeward, Snorri T. Sigurdsson, and Thomas F. Prisner Magn. Reson., 6, 281–315, https://doi.org/10.5194/mr-6-281-2025, 2025 Pulsed electron paramagnetic resonance can measure distances and orientation between two paramagnetic markers. If they are rigidly attached to a biomolecule, advanced insights into the structure and dynamics of the biomolecule follow. We used chirp pulses to perform real two-dimensional experiments with much shorter experimental time compared to experiments with monochromatic microwave pulses. We also present new pulse sequences and give a detailed protocol for setting up such experiments. Tue, 02 Dec 2025 22:23:44 +0100 https://doi.org/10.5194/mr-6-273-2025 Long-lived states involving a manifold of fluorine-19 spins in fluorinated aliphatic chains Coline Wiame, Sebastiaan Van Dyck, Kirill Sheberstov, Aiky Razanahoera, and Geoffrey Bodenhausen Magn. Reson., 6, 273–279, https://doi.org/10.5194/mr-6-273-2025, 2025 In achiral polyfluoroalkyl substances with two to three CF₂ groups, long-lived ¹⁹F spin states (TLLS) were measured and found to last about three times longer than T₁ in a static 11.6 T field. These lifetimes are sensitive to macromolecular binding, making them useful for screening fluorinated drugs. Mon, 24 Nov 2025 22:23:44 +0100 https://doi.org/10.5194/mr-6-257-2025 γ effects identify preferentially populated rotamers of CH2F groups: side-chain conformations of fluorinated valine analogues in a protein Elwy H. Abdelkader, Nicholas F. Chilton, Ansis Maleckis, and Gottfried Otting Magn. Reson., 6, 257–272, https://doi.org/10.5194/mr-6-257-2025, 2025 The small protein GB1, where all valine residues were replaced by fluorinated analogues containing one or two CH2F groups, produces 19F NMR (nuclear magnetic resonance) spectra with exceptional resolution. We establish a convenient strategy for their assignment and analyse the rotameric states of the CH2F groups by virtue of three-bond coupling constants and a γ effect on 13C chemical shifts, which is underpinned by DFT (density functional theory) calculations. Transient fluorine–fluorine contacts are documented by through-space 19F–19F couplings. Mon, 17 Nov 2025 22:23:44 +0100 https://doi.org/10.5194/mr-6-243-2025 Quantifying the carbon footprint of conference travel: the case of NMR meetings Lucky N. Kapoor, Natália Ružičková, Predrag Živadinović, Valentin Leitner, Maria Anna Sisak, Cecelia Mweka, Jeroen Dobbelaere, Georgios Katsaros, and Paul Schanda Magn. Reson., 6, 243–256, https://doi.org/10.5194/mr-6-243-2025, 2025 By reviewing attendee lists of 10 MR (magnetic resonance) meetings over the last year, we estimate the climate footprint of conferences and explore possibilities to reduce it. This paper will facilitate discussions about possible actions the community may take. Mon, 10 Nov 2025 22:23:44 +0100 https://doi.org/10.5194/mr-6-229-2025 A fast sample shuttle to couple high and low magnetic fields and applications in high-resolution relaxometry Jorge A. Villanueva-Garibay, Andreas Tilch, Ana Paula Aguilar Alva, Guillaume Bouvignies, Frank Engelke, Fabien Ferrage, Agnes Glémot, Ulric B. le Paige, Giulia Licciardi, Claudio Luchinat, Giacomo Parigi, Philippe Pelupessy, Enrico Ravera, Alessandro Ruda, Lucas Siemons, Olof Stenström, and Jean-Max Tyburn Magn. Reson., 6, 229–241, https://doi.org/10.5194/mr-6-229-2025, 2025 Investigating NMR (nuclear magnetic resonance) phenomena at variable magnetic fields is useful and insightful for hyperpolarization and molecular dynamics in particular. To benefit from high-resolution at high magnetic fields, field-dependent investigations can be performed using a high-field NMR spectrometer, with a sample shuttle apparatus for field cycling. Here, we introduce a new design of a sample shuttle which is fast, reliable, and narrow. We show a series of applications involving small molecules and a protein in solution. Wed, 03 Sep 2025 22:23:44 +0200