Square planar Pd(II)/oximate complexes as 'metalloligands' for the directional assembly of 4f-metal ions: a new family of {LnPd} (Ln = lanthanide) clusters exhibiting slow magnetization relaxation.

A relatively unexplored approach in heterometallic chemistry of transition metals and lanthanides has been developed toward the controlled synthesis of a new family of linear heterotrinuclear Ln(III)-Pd(II)-Ln(III) complexes with the general formula [LnPd(pao)(NO)(MeOH)(HO)]·[Pd(pao)], where Ln = Dy (2), Gd (3), Er (4) and Yb (5). This strategy was based on the diamagnetic 'metalloligand' [Pd(pao)] (1), where pao is the anion of 2-pyridinealdoxime, containing two dangling oximate O-atoms which were to each other and available for binding with oxophilic lanthanide ions. Because of their -configuration, the [Pd(pao)] 'metalloligand' was able to direct the binding of two {Ln(NO)(MeOH)(HO)} units on opposite sites, thus yielding the reported trinuclear {Ln-Pd-Ln} clusters.

A Nanosized {Ni } Cluster with a 'Flying Saucer' Topology Exhibiting Slow Relaxation of Magnetisation Phenomena at Both 15 K and 1.3 K.

A high-nuclearity {Ni} complex (1) with a unique 'flying saucer' motif has been prepared from the organic chelate, α-methyl-2-pyridine-methanol (mpmH), in conjunction with bridging azido (N ) and peroxido (O ) ligands. Magnetic susceptibility measurements revealed the presence of both ferro- and antiferromagnetic exchange interactions between the metal centres in 1, and the stabilization of spin states with appreciable S values at two different temperature regimes. The end-on bridging azido and alkoxido groups are in all likelihood the ferromagnetic mediators, while the η:η:μ-bridging peroxides most likely promote the antiparallel alignment of the metals' spin vectors, yielding an overall non-zero spin ground state for the centrosymmetric compound 1.

Elevating the Performance of Heterometallic 3d/4f SMMs: The Role of Diamagnetic Co and Zn Ions in Magnetization Dynamics.

Recent advances in the synthesis of 3d/4f Single-Molecule Magnets (SMMs) have revealed the effective role of incorporating diamagnetic Co or Zn ions to enhance the magnetic properties of Ln ions. This concept highlights notable examples of Co/Ln and Zn/Ln SMMs documented in the recent literature, illustrating how the selection of various peripheral and/or bridging ligands can modulate the magnetic anisotropy of 4f metal ions, thereby increasing their energy barriers.

Peripheral site modification in a family of dinuclear [Dy(hynad)(NO)(sol)] single-molecule magnets bearing a {Dy(μ-OR)} diamond-shaped core and exhibiting dissimilar magnetic dynamics.

The first use of the organic chelate -hydroxy-1,8-naphthalimide (hynadH) in Dy chemistry has unveiled access to a synthetic 'playground' composed of four new dinuclear complexes, all of which possess the same planar {Dy(μ-OR)} diamond-shaped core, resulting from the bridging and chelating capacity of the hynad groups. The structural stability of the central {Dy} core has allowed for the modulation of the peripheral coordination sites of the metal ions, and specifically the NO/hynad ratio of capping groups, thus affording the compounds [Dy(hynad)(NO)(DMF)] (1), (MeN)[Dy(hynad)(NO)] (2), [Dy(hynad)(NO)(HO)] (3), and [Dy(hynad)(HO)] (4). Because of the chemical and structural modifications in the series 1-4, the Dy coordination polyhedra are also dissimilar, comprising the muffin (1 and 3), tetradecahedral (2), and spherical tricapped trigonal prismatic (4) geometries.