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News

August 2026 | Luminescent Chiral Polyoxometalate Networks
'Here we report a series of all-inorganic lanthanide-containing polyoxometalate (Ln−POM) hybrid clusters, featuring a rare 6:2 lanthanide-to-POM motif. The clusters consist of a hexanuclear {Ln6(μ₃-OH)₃(H₂O)₉}¹⁵⁺ unit sandwiched between two achiral trilacunary {A-α-SiW₉O₃₄}^10- polyanions, forming a robust three-dimensional chiral network with srs topology. The solid-state temperature-dependent photoluminescence studies of the Eu(III)-analogue underscores the utility of Eu(III)-based emission as a sensitive probe of site symmetry and dynamic structural modulations.
DOI:https://doi.org/10.1021/acs.inorgchem.6c01507

Visual Representation of six lanthanide ions sandwhiched between two large POM units.

Picutre of a saddle-shaped molecules with alternating Ni and Dy ions bridged through different organic molecules.

August 2026 | Large carbonate-bridged Ni-4f cluster where the Ni^II ions determine the spin structure
A combined experimental and theoretical study on a {Ni^II₈Ln^III₄} cluster (with Ln^III = Y^III, Gd^III and Dy^III) reveals a spin structure dominated by the strong Ni-based exchange coupling. This helps to the rationalize the µ-SQUID magnetization loops.
DOI:https://doi.org/10.1002/chem.71499

July 2026 | Proposing an experiment to directly measure giant toroidal moment in a Fe-Dy nano-ring
The ground state of an {Fe^III₁₀Dy^III₁₀} ring was calculated to be a giant toroidal moment taken into account ca. 62 billion states. As a result of the large nano-scale radius this compound may for the first time be amenable for the direct experimental observation of a toroidal moment using femtosecond laser pulses.
DOI:https://doi.org/10.1038/s41467-026-75612-6

On the left, a visual representation of the 62 billion spin states through two graphs that plot the Ising spinstate index against the relative energy. On the right pictures of the resulting spin waves determined by their angular momentum characterized as s, p, d, f, g and h waves-

Picture of a highly symmetric unit cell of a Dy2-dimer. Clearly visbile are four cavities in which highly disordered CCl4-molecules are positioned.

July 2026 | Highly symmetric halogen bonding network in a Dy-SMM
Solvent-mediated halogen bonding was identified in a Dy2 dimer SMM and quantified using quantum chemical calculations. The network result in a stabilization energy of 75-81 kJ/mol.
DOI:https://doi.org/10.1002/zaac.70181

June 2026 | Benchmarking 4f-exchange couplings
We investigated 27 Gd₂ molecules with Broken-Symmetry DFT establishing the surprisingly high precision of these calculations compared to experimental evidence. With the right setup, Mean Absolut Errors smaller than 0.02 cm^-1 for the coupling can be achieved. This work was published in the Special Issue for Annies 65^th birthday and is the cover of the June edition of Magnetochemistry.
DOI:https://doi.org/10.3390/magnetochemistry12060067

April 2026 | ¹⁶¹Dy Mößbauer spectroscopy as new tool to identify magnetic transitions in SMTs
A {Co^III₃Dy^III₃} cluster is characterized using both randomly oriented powder samples as well as single crystal measurements to reveal a toroidal ground state. The Boltzmann distribution-independent ¹⁶¹Dy Synchrotron Mößbauer Spectroscopy (SMS) hereby is identified as a useful way to gain information on magnetic transitions.
DOI:https://doi.org/10.1038/s41467-026-71058-y

April 2026 | Symmetry, Magnetism and Luminescence combined
In a study with the group of Mario Ruben, we could analyze the combined magnetic and luminesence data of a Dy-SIM in a multiconfigurational approach. This work was choosen as this issues cover of Dalton Transactions.
DOI:https://doi.org/10.1039/D6DT00081A

This cover shows how a laser points at a molecule which swims on the surface of a lake. It hits the molecule and a fish labeled C2v is jumping out of the water.

December 2025 | Radical strait-jacket leads to quenched QTM
Radical-radical interactions in {Dy^III₂(Rad)₄} dimer lead to ultrashort Dy-Dy distance and strong dipolar field quenching QTM. Doping the compound with Y^III turns QTM back on.
DOI:https://doi.org/10.1021/acs.inorgchem.5c04406

July 2025 | The influence of a bromine atom
We report the synthesis of two novel Er6 clusters where one uses a bromine substituted ligand. As a result the bromine containing compound forms a 7-connected tetragonal network through halogen-halogen bonding. The stabilisation of the cluster was investigated using quantum chemical calculations which reveal interactions between the halogen-halogen bonds. This is the first report of such cooperative effects in an inorganic coordination cluster.
DOI:https://doi.org/10.1021/acs.cgd.5c00517

A Picture showing three circles. In the left circle, a cardboard box is filled with Er6 prisms and Br atoms. The second circle shows a connection between eight Br-atoms. The last pictures shows that one Er6-prism is connected to seven other using the Br halogen bonds.

a complete hysteresis loop for a Spin-Crossover compound can be disrupted by adding a bromine atom to the ligand backbone.

July 2025 | Disrupting Spin-Crossover
In a modification of our previously published Fe(III) compound exhibiting sharp, complete and hysteretic SCO 10.1039/D4NJ03532A, we report the isostructural mononuclear Fe(III) compound with a bromine atom added to the ligand. The spin transition is now extremely broad and incomplete with the compound not being high-spin at 300 K.
DOI:https://doi.org/10.1039/D5NJ02493E

Older News (expand)

April 2025 | Vanadium Butterflies!
Here we report a series type II butterfly complexes using V(III) ions. This not only extends the butterfly testbed system towards the earlier 3d transition metal ions but also allowed us to study the interplay of magnetic single ion anisotropies and 3d-4f exchange interactions using a mixture of magnetometry (SQUID and µSQUID) and high frequency/high field EPR.
DOI:https://doi.org/10.1002/ceur.202500011

Picture showing a butterfly with V3-ions on the wingtips and lanthanide ions on the body. Above, a scheme of the intercation mechanism involving the interaction of V-3d orbitals with both 4f and 5d orbitals of the lanthanide are shown. Furthermore, the coupling strength against the lanthanides Tb, Ho, Er and Tm is plotted.

A white and purple certificate dedicated to Jonas Braun and signed by Prof. Carlos J. Gomez Garcia.

March 2025 | Outstanding Reviewer Award
Dr. Jonas Braun has been awarded the Outstanding Reviewer Award of Magnetochemistry! Read more about it here:
magnetochemistry

December 2024 | The Last Piece to Understand a Frustrated Fe₇ Cartwheel Cluster
In this publication we confirm the postulated SMM behaviour of a frustrated Fe7 compound via low-temperature SQUID magnetometry and Mössbauer spectroscopy. We are furthermore able to confirm the previously reported frustrated spin structure.
DOI:https://doi.org/10.1021/acs.inorgchem.4c04191

Picture showing the molecular structure of a Iron 7 Cluster with blue arrows corresponding to the respective spins.

November 2024 | POMs for Cathode-Coating
The cycling performance and stability of Ni-rich NCM851005 cathodes have been enhanced through a polyoxovanadate coating. This approach has shown effectiveness in both liquid- and solid-state batteries, contributing to the development of more durable energy storage solutions.
DOI:https://doi.org/10.1002/batt.202400601

NCM particles plus polyoxovanadate give coated NCM particles. A graph shows the increased retention of capacity over the number of cycles.

The Susceptibility graphs of two dinuclear Dysprosium compounds show either ferromagnetic coupling or antiferromagnetic coupling depending on the ion bridging the atoms.

October 2024 | Effect of Rigidity of Bridging Ligands between Dy(III) ions
Here we report two dinuclear Dy(III) compounds which differ only in their bridging ligands (fluoride vs peroxide). The difluorido-bridged compound is ferromagnetically coupled only shows very weak SMM behaviour whereas the peroxide-bridged compound, owing to its rigidity as a result of the O-O bond, shows dominant antiferromagnetic exchange and good SMM behaviour. The reason for the latter is likely the modulation of the phonon spectrum.
DOI:https://doi.org/10.1002/chem.202403002

October 2024 | Birthday Symposium
We are celebrating Annie Powells 65^th birthday with a two day symposium on 4f-chemistry in collaboration with the "4f for future"-CRC. Check out more on our website here.

Flyer containing Information about the event in low resolution.

susceptibility versus temperature graph for the presented Spin-Crossover compound.

September 2024 | Mononuclear Fe(III)-Spin Crossover
This publication reports the study of the spin state of a mononuclear spin crossover (SCO) compound using SQUID magnetometry and Mössbauer spectroscopy in a collaboration between Addis Adaba (Ethiopia), Kaiserslautern and Karlsruhe. The complex exhibits an abrupt SCO transition and open hysteresis between 125 and 152K.
DOI:https://doi.org/10.1039/D4NJ03532A

August 2024 | Book Chapter – 4f SMMs
In this book chapter we describe the development of 4f-based single molecule magnets since their discovery and the strategies on how to obtain high-performance SMMs highlighting the importance of female scientists in the field. Looking forward challenges and opportunities in this research area are outlined, consisting of designing multifunctional SMM-based materials and the necessary multitechnique approaches to characterise them.
DOI:https://doi.org/10.1016/bs.hpcre.2024.07.001

Picture showing the molecular structure of different 4f-Single-Molecule-Magnets.

July 2024 | Cover Feature: On the Interaction of Light and Magnetism
This cover feature represents an SMM which can show altered magnetic properties after photoexcitation. To study such effects experiments on multiple timescales are necessary.
DOI:https://doi.org/10.1002/chem.202402506

A picture showing a Ln10Fe10-ring on a dark background. Bihind it are pictures of a magnetic field and a red laser.

May 2024 | Concept Article – Multitechnique Approach on Various Timescales
In this concept article the importance of combining experiments on various timescales from femtoseconds to seconds in order to understand the behaviour of photoexcited SMMs is highlighted and an outlook given on how to advance research in this area.
DOI:https://doi.org/10.1002/chem.202400977

March 2024 | Efficient MCE in a Gd8 cluster
Here we report an octanuclear gadolinium coordination cluster with essentially uncoupled Gd^III ions. This leads to a very efficient magneto caloric effect (MCE) making this compound a candidate as a molecular magnetic refrigerant.
DOI:https://doi.org/10.3390/ijms25010264

February 2024 | Rationalisation of exotic spin structures
In this communication we present a study on a nanoscale saddle-shaped Fe8Dy12 cluster with an exotic nested spin structure including toroidal and spin-ice-like contributions and provide insights into the resulting magnetic behaviour.
DOI:10.1039/d3dt04141g

January 2024 | Polyoxometalate-loaded silica particles
In our new paper, we explore the encapsulation of polyoxometalates in mesoporous silica-nanoparticles and printing them on alkene functionalized surfaces for amine-ene immobilization.
DOI:https://doi.org/10.1038/s41598-023-50846-2

April 2023 | Anisotropic Gadolinium
In this project we are showing that a small anisotropy of otherwise isotropic Gadolinium ions can lead to slow relaxation of magnetization.
DOI:10.1021/acs.inorgchem.3c00042