An 'Intermetallic' Molecular Nanomagnet with the Lanthanide Coordinated Only by Transition Metals

The best performing molecular nanomagnets are currently designed by carefully arranging p-element donor atoms (usually carbon, nitrogen and/or oxygen) around the central magnetic ion. Inspired by the structure of the hardest intermetallic magnet SmCo5, we have demonstrated a nanomagnetic molecule where the central lanthanide (Ln) ion Er is coordinated solely by three transition metal (TM) ions in a perfectly trigonal planar fashion. The molecule [Er(ReCp2)3] (ErRe3) constitutes the first example of a molecular nanomagnet (MNM; or single molecule magnet SMM) with unsupported Ln-TM bonds and paves the way towards molecular intermetallics with strong direct magnetic exchange interactions. Such interactions are believed to be crucial for quenching the quantum tunneling of magnetization which limits the application of Ln-SMMs as sub-nanometer magnetic memory units.

The Use of Hirshfeld Surface Analysis Tools to Study the Intermolecular Interactions in Single Molecule Magnets

Intermolecular interactions have proved to play an important role in properties of SMMs such as quantum tunneling of magnetization (QTM), and they also reduce the rate of magnetic relaxation, as through the influence they have on QTM, they quicken the reverse of magnetization. In addition, they are considered as the generative cause of the exchange-biased phenomenon. Using the Hirshfeld analysis tools, all the intermolecular interactions of a molecule and its neighbors are revealed, and this leads to a systematic study of the observed interactions, which could probably be helpful in other studies, such as theoretical calculations. In addition, they could be helpful to design new systems because intermolecular interactions in SMMs have been proposed as a probable tool to monitor their properties. The observation of characteristic patterns on the Hirshfeld Surfaces (HS) decorated with different properties makes easier the recognition of possible structural pathways for the different types of interactions of a molecule with its surrounding.

The anisotropy of internal magnetic field on central ion is capable of imposing great impact on the quantum tunneling of magnetization of Kramers single-ion magnet

In this work, a theoretical method, taking into account the anisotropy of internal magnetic field (~Bint), is proposed to predict the rate of quantum tunneling of magnetization (QTM), i.e., τ-1QTM,...

High-Coordinate Mononuclear Ln(III) Complexes: Synthetic Strategies and Magnetic Properties

Single-molecule magnets involving monometallic 4f complexes have been investigated extensively in last two decades to understand the factors that govern the slow magnetization relaxation behavior in these complexes and to establish a magneto-structural correlation. The prime goal in this direction is to suppress the temperature independent quantum tunneling of magnetization (QTM) effect via fine-tuning the coordination geometry/microenvironment. Among the various coordination geometries that have been pursued, complexes containing high coordination number around Ln(III) are sparse. Herein, we present a summary of the various synthetic strategies that were used for the assembly of 10- and 12-coordinated Ln(III) complexes. The magnetic properties of such complexes are also described.

Zero-field slow relaxation of magnetization in cobalt(ii) single-ion magnets: suppression of quantum tunneling of magnetization by tailoring the intermolecular magnetic coupling

Quenching of quantum tunneling of magnetization was observed in a tetrahedral cobalt(ii) complex with 1-D chain hydrogen-bond networks by partially substituting the CoII ion with the ZnII ion, up to 33%.

A method to predict both the relaxation time of quantum tunneling of magnetization and the effective barrier of magnetic reversal for a Kramers single-ion magnet

A method to predict the relaxation time of quantum tunneling of magnetization and the magnetic reversal barrier with efficiency and reliability.

Influence of magnetic dilution on relaxation processes in a solid solution comprising tetrahedral Co/ZnII complexes

Dilution with diamagnetic species in a SIM solid solution leads to an increase in relaxation times at low temperatures and monotonously reduces the probability of quantum tunneling of magnetization and the direct process.

Fine tuning of magnetization relaxation parameters of the DyO+ single ion magnet in a hydroxy/fluoro-apatite solid solution

Variation of the crystal environment of DyO+ regulates the energy barrier for magnetization reversal and the rate of quantum tunneling of magnetization.