Molecular Magnetism of Lanthanides Complexes and Networks

Abstract

Lanthanides ions allows for the design of remarkable magnetic compounds with unique magnetic properties. One of their assets is that they can give rise easily to multi-functional materials. Such multi-functionality is found in the collection of papers of this Special Issue with contributions that highlight the unprecedented magnetic properties of lanthanide-based molecules together with chirality [1], luminescence [2,3] or electrical conductivity properties [4]. Innovative synthetic routes such as the use of helical [1,5] or protonated ligands [6] together with cutting edge characterization techniques of 4f-SMM are presented [7].First of all, this Issue features a remarkable review article from Oliver Waldman and co-workers [7] that highlights the power of neutron scattering studies for the understanding of the magnetic behavior of 4f-SMMs. This extended and remarkably accurate work provides a deep and comprehensive perspective on this technique by analyzing, among others, one of the most famous molecules in our field, the Tb 2 (µ-N 2 3− ) dimer.Then, a study of Jerôme Long and co-workers [3] details how the analysis of luminescent properties of Dy-SMMs can be useful for understanding their magnetic properties. The authors use the very simple molecule [Dy(NO 3 ) 3 (H 2 O) 4 ]·2H 2 O which, though often used as a precursor in the design of Dy-SMM, has never been deeply characterized.Miki Hasegawa, Takashi Kajiwara and co-workers [5] present a nice 4f-SMM family based on a helical ligand in which, surprisingly, not only the Dy III but also the Nd III derivative show SMM behavior [5]. Helicity is also the topic of the work of Boris Le Guennic and co-workers [1] in which SMM behavior is observed on a racemic form of a helicene-based molecule with a remarkable magnetic hysteresis opening.Albert Escuer, Spyros Perlepes and co-workers [6] report a new approach to the widely used triethanolamine ligand that gives rise to a family of Ln III complexes in which the Dy III derivative behave as a SMM.Pierre Rabu, Emilie Delahaye and co-workers [2] show how synthetic conditions can influence the creation of magnetic hybrid networks in which the Sm III and Pr III adducts depict luminescent properties.Masahiro Yamashita and co-workers [4] present a very appealing hybrid material in which partially oxidized BEDT-TTF molecules crystallize together with Dy III precursors to form a compound in which both SMM behavior and electrical conductivity can be observed.

High Luminance of Heterolanthanide-Based Molecular Alloys by Phase-Induction Strategy

“…Indeed, it is commonly admitted that, because of the shielded character of the 4f valence orbital of lanthanide ions, Ln−O−C−O−Ln bridges are inefficient for transmitting electronic effects. 74,75 To the contrary, Ln−O−Ln bridges can transmit them more efficiently 76 as we observed on coordination polymers made of ferromagnetically coupled Dy 3+ ions. We can thus consider that such an "inorganic sublattice" that is more efficient for the transmission of electronic effect is a network made only of lanthanide and oxygen atoms bound together.…”

Eight-coordinate mono- and dinuclear Dy(iii) complexes containing a rigid equatorial plane and an anisobidentate carboxylate ligand in the axial position: synthesis, structure and magnetism

“…[1][2][3][4] Ever since the discovery of SMM behavior in the mononuclear [TbPc 2 ] − complex (Pc: phthalocyanine), 5 interest in Ln-based SMMs has been continuously growing in an unabated manner. [6][7][8][9][10] The inherently large single-ion anisotropy in lanthanide ions, owing to strong spin-orbit coupling (SOC) accompanied by a large spin ground state, makes them particularly appealing in the field of molecular nanomagnetism. 6,11,12 Although crystal field effects in lanthanide complexes are much smaller, they have a subtle and important influence in determining and harnessing the magnetic anisotropy in these molecular complexes.…”