DPG Phi
Verhandlungen
Verhandlungen
DPG

Dresden 2017 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MA: Fachverband Magnetismus

MA 20: Bio- and Molecular Magnetism

MA 20.1: Vortrag

Dienstag, 21. März 2017, 09:30–09:45, HSZ 301

Changing the Molecular Conformation of Endohedral Rare Earth Single-Molecule Magnets with Magnetic Torque — •Aram Kostanyan1, Rasmus Westerström2, Yang Zhang3, Alexey Popov3, and Thomas Greber11Physik-Institut, Uni Zürich, Winterthurerstr. 190,8057 Zürich, Switzerland — 2Division of Synchrotron Radiation Research, Department of Physics, Lund University, Lund, Sweden — 3Nanoscale Chemistry, IFW Dresden,Helmholtzstr. 20, 01069, Dresden, Germany

The endohedral unit of endohedral fullerenes exhibits thermally activated hopping motion between low-energy conformations. The motion ceases out at low temperatures locking the unit in a random state.

For single-molecule magnet HoLu2N@C80, the magnetic moment of Ho is aligned with the Ho-N axis due to strong ligand field imposed by the N3− ion. If the external magnetic field applies a torque on the magnetic moment of the Ho3+ ion it can be transferred to the encapsulated unit.

Field and temperature dependent measurements show a conformational change by means of magnetic torque on a single magnetic moment. At 1.8 K, the in-field cooled sample shows a magnetization curve that exceeds that of the zero-field cooled one. The difference does not scale with a single factor and increases with decreasing temperature sweep rate.

By means of a first order kinetics model, it is possible to determine the attempt frequency and activation energy for the hopping motion. It also allows to understand the non-linear field dependence of the effect.

100% | Mobil-Ansicht | English Version | Kontakt/Impressum/Datenschutz
DPG-Physik > DPG-Verhandlungen > 2017 > Dresden