Magnetic moments: The orientation of the title single‐molecule magnet was investigated by magnetic single crystal and luminescence characterization, supported by ab initio calculations, and was found to be governed by the position of the hydrogen atoms of the apical water molecules. This finding suggests that simple magneto‐structural correlations can give misleading clues for research in molecular magnetism as well as in the design of MRI contrast agents.

Spotting trends: Upon going from Tb(III) to Yb(III) centers in the complexes of the DOTA(4-) ligand, a reorientation of the easy axis of magnetization from perpendicular to parallel to the Ln-O bond of the apical water molecule is experimentally observed and theoretically predicted (SMM=single-molecule magnet). Only ions with an odd number of electrons show slow relaxation of the magnetization.

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Angular-resolved single-crystal magnetometry is a key tool to characterise lanthanide-based materials with low symmetry, for which conjectures based on idealised geometries can be totally misleading. Unfortunately the technique is strictly successful only for triclinic structures, thus reducing significantly its application. By collecting out-of-equilibrium magnetisation data the technique was extended to the orthorhombic organometallic Cp*ErCOT single-molecule magnet (SMM), thus allowing for the first time the reconstruction of the molecular anisotropy tensor notwithstanding the two molecular orientations in the crystal lattice. The results, flanked by state-of-the-art ab initio calculations, confirmed the expected orientation of the molecular easy axis of magnetisation and thus validated the synthetic strategy based on organometallic complexes of a single lanthanide ion.

The experimental investigation of the molecular magnetic anisotropy in crystals in which the magnetic centers are symmetry related, but do not have a parallel orientation has been approached by using torque magnetometry. A single crystal of the orthorhombic organometallic Cp*ErCOT [Cp*=pentamethylcyclopentadiene anion (C5Me5(-)); COT=cyclooctatetraenedianion (C8H8(2-))] single-molecule magnet, characterized by the presence of two nonparallel families of molecules in the crystal, has been investigated above its blocking temperature. The results confirm an Ising-type anisotropy with the easy direction pointing along the pseudosymmetry axis of the complex, as previously suggested by out-of-equilibrium angular-resolved magnetometry. The use of torque magnetometry, not requiring the presence of magnetic hysteresis, proves to be even more powerful for these purposes than standard single-crystal magnetometry. Furthermore, exploiting the sensitivity and versatility of this technique, magnetic anisotropy has been investigated up to 150 K, providing additional information on the crystal-field splitting of the ground J multiplet of the Er(III) ion.

The present work reports the application of RF-magnetron sputtering technique to realize CsPbBr 3 70 nm thick films on glass substrate by means of a one-step procedure. The obtained films show highly uniform surface morphology and homogeneous thickness as evidenced by AFM and SEM investigations. XRD measurements demonstrate the presence of two phases: a dominant orthorhombic CsPbBr 3 and a subordinate CsPb 2 Br 5 . Finally, XPS data reveals surface bromine depletion respect to the stoichiometrical CsPbBr 3 composition, nevertheless photoluminescence spectroscopy results confirm the formation of a highly luminescent film. These preliminary results demonstrate that our approach could be of great relevance for easy fabrication of large area perovskite thin films. Future developments, based on this approach, may include the realization of multijunction solar cells and multicolor light emitting devices.

Trendforschung: Beim Wechsel von TbIII‐ zu YbIII‐Zentren der Komplexe des DOTA4−‐Liganden wird experimentell beobachtet und theoretisch vorausgesagt, dass sich die Reorientierung der Magnetisierung des apikalen Wassermoleküls ändert, und zwar von senkrecht zu parallel zur Ln‐O‐Bindung (siehe Bild). Nur Ionen mit einer ungeraden Elektronenzahl zeigen eine langsame Relaxation der Magnetisierung. SMM=Einzelmolekülmagnet.

The synthesis and the chemisorption from solution of a terbium bis-phthalocyaninato complex suitable for the functionalization of lanthanum strontium manganite (LSMO) are reported. Two phosphonate groups are introduced in the double decker structure in order to allow the grafting to the ferromagnetic substrate actively used as injection electrode in organic spin valve devices. The covalent bonding of functionalized terbium bis-phthalocyaninato system on LSMO surface preserves its molecular properties at the nanoscale. X-ray photoelectron spectroscopy confirms the integrity of the molecules on the LSMO surface and a small magnetic hysteresis reminiscent of the typical single molecule magnet behavior of this system is detected on surface by X-ray magnetic circular dichroism experiments. The effect of the hybrid magnetic electrode on spin polarized injection is investigated in vertical organic spin valve devices and compared to the behavior of similar spin valves embedding a single diamagnetic layer of alkyl phosphonate molecules analogously chemisorbed on LSMO. Magnetoresistance experiments have evidenced significant alterations of the magneto-transport by the terbium bisphthalocyaninato complex characterized by two distinct temperature regimes, below and above 50 K, respectively.