High‐ T _c Ordered Molecular Magnets

How to Make a Better Magnet? Insertion of Additional Bridging Ligands into a Magnetic Coordination Polymer

“…The additional functionalities co-exist or are strongly coupled with the magnetic ordering, providing a convenient route to multifunctionality [1]. In terms of future technological applications, it is crucial to develop new strategies towards higher magnetic ordering temperatures in molecular magnets [2] to eliminate the need for expensive cooling resources like liquid helium. Efforts thus far have focused mainly on Prussian blue analogs [3] and cyanido-bridged materials based on hepta-or octacyanidometallates of 4d and 5d metal ions [4,5].…”

Self-Assembled Tetranuclear Square Complex of Chromium(III) Bridged by Radical Pyrazine: A Molecular Model for Metal–Organic Magnets

“…Hence, the metal-radical approach has been extensively used in the field of molecular magnetism, where organic radicals are typically isolated before their subsequent assembly with metal ion centers. , Frequently, radical ligands have also been introduced through post-synthetic redox treatment of complexes and materials containing closed-shell ligands. − An alternative, however, to save time, reactants, and reduce chemical waste, is to explore the possibility of in-situ redox processes between the metal ion and the ligand during the synthesis. By rationally selecting the metal/ligand pair based on their respective redox properties, both energies and overlaps of magnetically relevant molecular orbitals (MOs) can be tuned to attain the desired magnetic and transport properties. − Through this approach, molecule-based magnets with critical temperatures above room temperature have been obtained from the tetracyanoethylene (TCNE) radical and its analogues. − …”

Printing Air-Stable High-TcMolecular Magnet with Tunable Magnetic Interaction

“…We further examine the role of zeolitic water in the reversible magnetism control of thermally stable compound 1 in which the zeolitic water molecules randomly occupy interstitial sites to lower the magnetic ordering temperature . The structural vacancy in such a compound enables the absorption and desorption of water molecules, which in turn, could lead to dynamical and reversible tunability of magnetic exchange interactions for the proof-of-concept demonstration of stimuli directed energy conversion and cooling devices. − , Figure a shows temperature dependence of the magnetization ( M – T ) of compound 1 at different relative humidity (RH). Under 0% RH, it shows a typical magnetic phase transformation between low-temperature ferrimagnetic phase and high-temperature paramagnetic phase with a T c of 360 K. The T c of compound 1 can decrease from 360 K (0% RH) to 304 K (80% RH) (Figure b).…”