Largest magnetic anisotropy of a molecule measured at BESSY II
THz-EPR setup in the experimental hall of BESSY II. © HZB
The magnetic properties of the investigated bismuth complex (center) were investigated using THz-EPR spectroscopy at BESSY II. The method uses electromagnetic radiation from the THz to the infrared range in combination with high magnetic fields. © HZB
At the Berlin synchrotron radiation source BESSY II, the largest magnetic anisotropy of a single molecule ever measured experimentally has been determined. The larger this anisotropy is, the better a molecule is suited as a molecular nanomagnet. Such nanomagnets have a wide range of potential applications, for example, in energy-efficient data storage. Researchers from the Max Planck Institute for Kohlenforschung (MPI KOFO), the Joint Lab EPR4Energy of the Max Planck Institute for Chemical Energy Conversion (MPI CEC) and the Helmholtz-Zentrum Berlin were involved in the study.
The research involved a bismuth complex synthesized in the group of Josep Cornella (MPI KOFO). This molecule has unique magnetic properties that a team led by Frank Neese (MPI KOFO) recently predicted in theoretical studies. So far, however, all attempts to measure the magnetic properties of the bismuth complex and thus experimentally confirm the theoretical predictions have failed.
This important step has now been achieved by using THz electron paramagnetic resonance spectroscopy (THz-EPR) at the synchrotron radiation source BESSY II, which is operated by the HZB in Berlin.
“The results show in a fascinating way that our method can be used to determine extremely high values of the magnetic anisotropy with high accuracy. Through our cooperation with scientists from fundamental research, we are thereby making a great step forward in the understanding of this class of materials,” says Tarek Al Said (HZB), first author of the study, which was recently published in the renowned Journal of the American Chemical Society.
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- New method shows how molecular switches are influenced by their neighborsResearchers at Friedrich Schiller University Jena and the Helmholtz Centre Berlin (HZB) have, for the first time, been able to directly observe how the environment surrounding a molecular switch influences its electronic structure. Molecular switches are molecules that can be switched between two states by external influences such as changes in temperature—similar to a switch with the positions »On« and »Off«. Such molecules are being investigated as potential building blocks for future data storage devices or sensor materials. Using magnetic-field-dependent terahertz spectroscopy, the researchers have now, for the first time, been able to distinguish whether neighbouring molecules in a material are in the same or different states. The results have been published in the journal »Angewandte Chemie International Edition«.
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