Dinuclear Dysprosium Compounds: The Importance of Rigid Bridges.

We report the synthesis, structures and magnetic behaviour of two isostructural dinuclear Dy complexes where the metal ions of a previously reported monomeric building block are connected by a peroxide (O ) or a pair of fluoride (2×F) bridges. The nature of the bridge determines the distance between the metal ion dipoles leading to a dipolar coupling in the peroxido bridged compound of only ca. 70 % of that in the bis-fluorido bridged dimer.

LnDOTA puppeteering: removing the water molecule and imposing tetragonal symmetry.

Complexes of lanthanide(iii) ions (Ln) with tetraazacyclododecane-,','','''-tetraacetate (DOTA) are a benchmark in the field of magnetism due to their well-investigated and sometimes surprising features. calculations suggest that the ninth ligand, an axial water molecule, is key in defining the magnetic properties because it breaks the potential symmetry of the resulting complexes. In this paper, we experimentally isolate the role of the water molecule by excluding it from the metal coordination sphere without altering the chemical structure of the ligand.

Terminal Ligand and Packing Effects on Slow Relaxation in an Isostructural Set of [Dy(H dapp)X ] Single Molecule Magnets*.

We report three structurally related single ion Dy compounds using the pentadentate ligand 2,6-bis((E)-1-(2-(pyridin-2-yl)-hydrazineylidene)ethyl)pyridine (H dapp) [Dy(H dapp)(NO ) ]NO (1), [Dy(H dapp)(OAc) ]Cl (2) and [Dy(H dapp)(NO ) ]Cl (NO ) (3). The (H dapp) occupies a helical twisted pentagonal equatorial arrangement with two anionic ligands in the axial positions. Further influence on the electronic and magnetic structure is provided by a closely associated counterion interacting with the central N-H group of the (H dapp).

Exploring the Vibrational Side of Spin-Phonon Coupling in Single-Molecule Magnets via Dy Nuclear Resonance Vibrational Spectroscopy.

Synchrotron-based nuclear resonance vibrational spectroscopy (NRVS) using the Mössbauer isotope Dy has been employed for the first time to study the vibrational properties of a single-molecule magnet (SMM) incorporating Dy , namely [Dy(Cy PO) (H O) ]Br ⋅2 (Cy PO)⋅2 H O ⋅2 EtOH. The experimental partial phonon density of states (pDOS), which includes all vibrational modes involving a displacement of the Dy ion, was reproduced by means of simulations using density functional theory (DFT), enabling the assignment of all intramolecular vibrational modes. This study proves that Dy NRVS is a powerful experimental tool with significant potential to help to clarify the role of phonons in SMMs.