Single molecule magnet with an unpaired electron trapped between two lanthanide ions inside a fullerene.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 28706223.
- Also identified by DOI 10.1038/ncomms16098 and PMC identifier 5519982.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Increasing the temperature at which molecules behave as single-molecule magnets is a serious challenge in molecular magnetism. One of the ways to address this problem is to create the molecules with strongly coupled lanthanide ions. In this work, endohedral metallofullerenes Y<sub>2</sub>@C<sub>80</sub> and Dy<sub>2</sub>@C<sub>80</sub> are obtained in the form of air-stable benzyl monoadducts. Both feature an unpaired electron trapped between metal ions, thus forming a single-electron metal-metal bond. Giant exchange interactions between lanthanide ions and the unpaired electron result in single-molecule magnetism of Dy<sub>2</sub>@C<sub>80</sub>(CH<sub>2</sub>Ph) with a record-high 100 s blocking temperature of 18 K. All magnetic moments in Dy<sub>2</sub>@C<sub>80</sub>(CH<sub>2</sub>Ph) are parallel and couple ferromagnetically to form a single spin unit of 21 μ<sub>B</sub> with a dysprosium-electron exchange constant of 32 cm<sup>-1</sup>. The barrier of the magnetization reversal of 613 K is assigned to the state in which the spin of one Dy centre is flipped.