title: One-dimensional supramolecular organization of single-molecule magnets.
abstract: An out-of-plane dimeric MnIII quadridentate Schiff-base compound, [Mn2(salpn)2(H2O)2](ClO4)2 (salpn(2-) = N,N'-(propane)bis(salicylideneiminate)), has been synthesized and structurally characterized. The crystal structure reveals that the [Mn2(salpn)2(H2O)2](2+) units are linked through weak H-bonds (OHwater...OPh) in one dimension along the c-axis, forming supramolecular chains. The exchange interaction between MnIII ions via the biphenolate bridge is ferromagnetic (J/kB = +1.8 K), inducing an ST = 4 ground state. This dinuclear unit possesses uni-axial anisotropy observed in the out-of-plane direction with DMn2/kB = -1.65 K. At low temperatures, this complex exhibits slow relaxation of its magnetization in agreement with a single-molecule magnet (SMM) behavior. Interestingly, the intermolecular magnetic interactions along the one-dimensional organization, albeit weak (J'/kB = -0.03 K), influence significantly the thermally activated and quantum dynamics of this complex. Thus, unique features such as M vs H data with multiple steps, hysteresis effects, and peculiar relaxation time have been explained considering SMMs in small exchange-field perturbations and finite-size effects intrinsic to the chain arrangement. The magnetic properties of this new complex can be regarded as an intermediate behavior between SMM and single-chain magnet (SCM) properties.
authors: Université Bordeaux 1, CNRS, Centre de Recherche Paul Pascal--UPR8641, 115 avenue du Dr. Albert Schweitzer, 33600 Pessac, France.
authors: Lollita
authors: L
authors: Lecren
authors: Wolfgang
authors: W
authors: Wernsdorfer
authors: Yang-Guang
authors: YG
authors: Li
authors: Alessandro
authors: A
authors: Vindigni
authors: Hitoshi
authors: H
authors: Miyasaka
authors: Rodolphe
authors: R
authors: Clérac