title: Single-molecule magnet behavior for an antiferromagnetically superexchange-coupled dinuclear dysprosium(III) complex.
abstract: A family of five dinuclear lanthanide complexes has been synthesized with general formula [Ln(III)(2)(valdien)(2)(NO(3))(2)] where (H(2)valdien = N1,N3-bis(3-methoxysalicylidene)diethylenetriamine) and Ln(III) = Eu(III)1, Gd(III)2, Tb(III)3, Dy(III)4, and Ho(III)5. The magnetic investigations reveal that 4 exhibits single-molecule magnet (SMM) behavior with an anisotropic barrier U(eff) = 76 K. The step-like features in the hysteresis loops observed for 4 reveal an antiferromagnetic exchange coupling between the two dysprosium ions. Ab initio calculations confirm the weak antiferromagnetic interaction with an exchange constant J(Dy-Dy) = -0.21 cm(-1). The observed steps in the hysteresis loops correspond to a weakly coupled system similar to exchange-biased SMMs. The Dy(2) complex is an ideal candidate for the elucidation of slow relaxation of the magnetization mechanism seen in lanthanide systems.
authors.affiliation: Department of Chemistry, University of Ottawa, 10 Marie-Curie, Ottawa, ON, K1N6N5, Canada.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Long
authors.forename: Fatemah
authors.initials: F
authors.lastname: Habib
authors.forename: Po-Heng
authors.initials: PH
authors.lastname: Lin
authors.forename: Ilia
authors.initials: I
authors.lastname: Korobkov
authors.forename: Gary
authors.initials: G
authors.lastname: Enright
authors.forename: Liviu
authors.initials: L
authors.lastname: Ungur
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wernsdorfer
authors.forename: Liviu F
authors.initials: LF
authors.lastname: Chibotaru
authors.forename: Muralee
authors.initials: M
authors.lastname: Murugesu