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News

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

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.