Impact of the coordination environment on the magnetic properties of single-molecule magnets based on homo- and hetero-dinuclear terbium(iii) heteroleptic tris(crownphthalocyaninate)

Rebecca J Holmberg; Marina A Polovkova; Alexander G Martynov; Yulia G Gorbunova; Muralee Murugesu

doi:10.1039/c6dt00777e

Impact of the coordination environment on the magnetic properties of single-molecule magnets based on homo- and hetero-dinuclear terbium(iii) heteroleptic tris(crownphthalocyaninate)

Dalton Trans. 2016 May 31;45(22):9320-7. doi: 10.1039/c6dt00777e.

Authors

Rebecca J Holmberg¹, Marina A Polovkova², Alexander G Martynov², Yulia G Gorbunova³, Muralee Murugesu¹

Affiliations

¹ Department of Chemistry and Biomolecular Sciences, and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada. m.murugesu@uottawa.ca.
² A. N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Leninsky Prosp. 31, Moscow 119071, Russia.
³ A. N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Leninsky Prosp. 31, Moscow 119071, Russia and N. S. Kurnakov Institute of General and Inorganic Chemistry RAS, Leninsky Prosp. 31, Moscow 119991, Russia.

PMID: 27184182
DOI: 10.1039/c6dt00777e

Abstract

A series of Tb(III) triple-decker heteroleptic crownphthalocyaninate complexes consisting of a homodinuclear compound [(15C5)4Pc]Tb[(15C5)4Pc]Tb(Pc) (), and two novel heterodinuclear compounds [(15C5)4Pc]Tb[(15C5)4Pc]Y(Pc), () and [(15C5)4Pc]Y[(15C5)4Pc]Tb(Pc) (), have been synthesized. All compounds were characterised using UV-Vis spectroscopy, HR-ESI-MS, MALDI-TOF-MS, and (1)H NMR spectroscopy, followed by exploration into the effects of lanthanide coupling and ligand field symmetry on the magnetic properties of these complexes using SQUID magnetometry. Magnetic measurements on the homonuclear Tb(III) complex () displayed non-negligible ferromagnetic coupling between magnetic ions, eliciting a high zero-field energetic barrier to the magnetic relaxation of Ueff = 229.9(0) K, while the heteronuclear Tb(III)/Y(III) complexes displayed single-ion field-induced slow relaxation of the magnetization; yielding energetic barriers of Ueff = 129.8(0) K for , and 169.1(8) K for .