title: The effect of crystal packing and Re(IV) ions on the magnetisation relaxation of [Mn6]-based molecular magnets.
abstract: The energy barrier to magnetisation relaxation in single-molecule magnets (SMMs) proffers potential technological applications in high-density information storage and quantum computation. Leading candidates amongst complexes of 3d metals ions are the hexametallic family of complexes of formula [Mn6 O2 (R-sao)6 (X)2 (solvent)y ] (saoH2 =salicylaldoxime; X=mono-anion; y=4-6; R=H, Me, Et, and Ph). The recent synthesis of cationic [Mn6 ][ClO4 ]2 family members, in which the coordinating X ions were replaced with non-coordinating anions, opened the gateway to constructing families of novel [Mn6 ] salts in which the identity and nature of the charge balancing anions could be employed to alter the physical properties of the complex. Herein we demonstrate initial experiments to show that this is indeed possible. By replacing the diamagnetic ClO4 (-) anions with the highly anisotropic Re(IV) ion in the form of [Re(IV) Cl6 ](2-) , the energy barrier to magnetisation relaxation is increased by up to 30 %.
authors.affiliation: EaStCHEM School of Chemistry, The University of Edinburgh, David Brewster Road, Edinburgh, EH9 3FJ, Scotland (UK). ebrechin@staffmail.ed.ac.uk.
authors.forename: José
authors.initials: J
authors.lastname: Martínez-Lillo
authors.affiliation: Fundació General de la Universitat de València (FGUV), Instituto de Ciencia Molecular (ICMol), Universitat de València, C/Catedrático José Beltrán n° 2, 46980 Paterna (València) (Spain).
authors.forename: Joan
authors.initials: J
authors.lastname: Cano
authors.affiliation: Institut Néel-CNRS, BP 166, 25 Avenue des Martyrs, 38042 Grenoble Cedex 9 (France).
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wernsdorfer
authors.affiliation: EaStCHEM School of Chemistry, The University of Edinburgh, David Brewster Road, Edinburgh, EH9 3FJ, Scotland (UK). lillo@uv.es.
authors.forename: Euan K
authors.initials: EK
authors.lastname: Brechin
keywords: density functional calculations; magnetisation relaxation; manganese; oximes; rhenium