Magnetic molecules on demand: the key role of inelastic neutron scattering and torque magnetometry

by Dr Mauro Perfetti (University of Copenhagen)

Monday 2 Jul 2018, 14:30 → 15:30 Europe/Berlin

HS 3 (Physics Department)

Total control over the electronic structure in molecular nanomagnets is the ultimate goal in the design of molecules with realizable applications in spin-based devices. Single-ion lanthanide systems are the most promising candidates for the next generation of single molecule magnets due to their exceptionally pronounced magnetic anisotropy [1]. We investigated the electronic structure and magnetic properties of a family of mononuclear lanthanide complexes [2]using an unprecedented combination of inelastic neutron scattering and single crystal cantilever torque magnetometry. The complementary information provided by these techniques was used to fully unravel the interplay between symmetry and magnetism. Indeed, we experimentally demonstrated that a threefold reduction of the undesirable tunnel splitting in a dysprosium single molecule magnet can be obtained by modifying the molecular symmetry [3]. Moreover, we discovered a class of molecules that can switch magnetic anisotropy simply controlling external stimuli like magnetic field and temperature [4].

 

 

1. Goodwin, C.A.; Ortu, F.; Reta, D.; Chilton, N.F.; Mills, D.P. Molecular magnetic hysteresis at 60 kelvin in dysprosocenium. Nature 2017, 548, 439.
2. Sørensen, M.A.; Weihe, H.; Vinum, M.G.; Mortensen, J.S.; Doerrer, L.H.; Bendix, J. Imposing high-symmetry and tuneable geometry on lanthanide centres with chelating pt and pd metalloligands. Chem. Sci. 2017, 8, 3566.
3. Sørensen, M.A.; Hansen, U.B.; Perfetti, M.; Pedersen, K.S.; Bartolomé, E.; Simeoni, G.G.; Mutka, H.; Rols, S.; Jeong, M.; Zivkovic, I., et al.Chemical tunnel-splitting-engineering in a dysprosium-based molecular nanomagnet. Nat. Commun. 2018, 9, 1292.
4. Perfetti, M.; Sørensen, M.A.; Hansen, U.B.; Bamberger, H.; Lenz, S.; Hallmen, P.P.; Fennell, T.; Simeoni, G.G.; Arauzo, A.; Bartolomé, J., et al.Magnetic anisotropy switch: Easy axis to easy plane conversion and vice versa. Adv. Funct. Mater. 2018, Accepted.