title: A SIM-MOF: three-dimensional organisation of single-ion magnets with anion-exchange capabilities.
abstract: The formation of a metal-organic framework (MOF) with nodes that have single-molecule magnet (SMM) behaviour has been achieved by using mononuclear lanthanoid analogues, also known as single-ion magnets (SIMs), which enormously simplifies the challenging issue of making SMM-MOFs. Here we present a rational design of a family of MOFs, [Ln(bipyNO)4](TfO)3⋅x solvent (Ln=Tb (1); Dy (2); Ho (3); Er (4); TfO=triflate), in which the lanthanoid centres have an square-antiprismatic coordination environment suitable for SIM behaviour. Magnetic measurements confirm the existence of slow magnetic relaxation typical of SMMs, which has been rationalised by means of a radial effective charge model. In addition, we have explored the incorporation of bulky polyoxometalates (POMs) into the cavities of the SIM-MOF by anion exchange, finding that they do not interfere with the slow magnetic relaxation. This demonstrates the robustness of the frameworks and opens the possibility of incorporating non-innocent anions.
authors.affiliation: Instituto de Ciencia Molecular (ICMol), Universidad de Valencia c/Catedrático José Beltrán, 2, 46980 Paterna (Spain).
authors.forename: José J
authors.initials: JJ
authors.lastname: Baldoví
authors.forename: Eugenio
authors.initials: E
authors.lastname: Coronado
authors.forename: Alejandro
authors.initials: A
authors.lastname: Gaita-Ariño
authors.forename: Christoph
authors.initials: C
authors.lastname: Gamer
authors.forename: Mónica
authors.initials: M
authors.lastname: Giménez-Marqués
authors.forename: Guillermo
authors.initials: G
authors.lastname: Mínguez Espallargas
keywords: anions; magnetic properties; metal-organic frameworks; polyoxometalates; single-molecule studies