title: Effect of f-f interactions on quantum tunnelling of the magnetization: mono- and dinuclear Dy(III) phthalocyaninato triple-decker single-molecule magnets with the same octacoordination environment.
abstract: The single-molecule magnet (SMM) behaviour of dinuclear Ln(III)-Pc triple-decker complexes (Dy(III)-Y(III): 1 and Dy(III)-Dy(III): 2) with the same octacoordination environment and slow magnetic relaxation behaviour were explained using X-ray crystallography and static and dynamic susceptibility measurements. In particular, interactions among the 4f electrons of dinuclear Dy(III)-Pc triple-decker type SMMs have never been discussed on the basis of the same octacoordination environment. Our results clearly show that the Dy(III) ion sites of 1 and 2 are equivalent, consistent with the crystal structure. 2 Exhibited ferromagnetic interaction between Dy(III) ions. This is clear evidence that the magnetic relaxation mechanism depends heavily on the dipole-dipole (f-f) interactions between the Dy(III) ions in the dinuclear systems. For both 1 and 2, quantum tunnelling of the magnetization (QTM) was observed. However, the magnetic relaxation time (τ) for 2 was one order of magnitude greater than that for 1, and single-component magnetic relaxation behaviour was explained. In other words, it is possible to use f-f interactions to increase τ by one order of magnitude.
authors.affiliation: Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan. kkatoh@m.tohoku.ac.jp yamasita@agnus.chem.tohoku.ac.jp.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Katoh
authors.forename: Rina
authors.initials: R
authors.lastname: Asano
authors.forename: Akira
authors.initials: A
authors.lastname: Miura
authors.forename: Yoji
authors.initials: Y
authors.lastname: Horii
authors.forename: Takaumi
authors.initials: T
authors.lastname: Morita
authors.forename: Brian K
authors.initials: BK
authors.lastname: Breedlove
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yamashita