Creation of a Field‐Induced Co(II) Single‐Ion Magnet by Doping into a Zn(II) Diamagnetic Metal–Organic Framework

Abstract

The combination of single‐ion magnets (SIMs) and metal–organic frameworks (MOFs) is expected to produce new quantum materials. The principal issue to be solved in this regard is the development of new strategies for the synthesis of SIM‐MOFs. This work demonstrates a new simple strategy for the synthesis of SIM‐MOFs where a diamagnetic MOF is used as the framework into which the SIM sites are doped. 1, 0.5, and 0.2 mol% of the Co(II) ions are doped into the Zn(II) sites of [CH6N3][ZnII(HCOO)3]. The doped Co(II) sites in the MOFs perform as SIM with a positive D term of zero‐field splitting. The longest magnetic relaxation time is 150 ms (0.2 mol% Co) at 1.8 K under a static field of 0.1 T. Temperature dependency of the relaxation time suggests suppressing magnetic relaxation by reduction of spin–spin interaction upon doping in the rigid framework. Thus, this work represents a proof of concept for the creation of a single‐ion doped magnet in the MOF. This simple synthetic strategy will be widely applied for the creation of quantum magnetic materials.

Metalation of metal–organic frameworks: fundamentals and applications

“…Pre-synthetic metalation, where the metal species are pre-anchored on the building blocks, commonly on the ligands, will be first described; post-synthetic modification (PSM), by post-anchoring of metal species into/onto either the ligand, metal node or pore, will be introduced next. The synthetic methods covered in this section include solvent thermal deposition (SIM), 73–77 atomic layer deposition (ALD), 78–81 ultrasonic and chemical deposition, in situ electro-synthesis strategies, and chemical vapor deposition.…”

An ethynyl-modified interpenetrated metal–organic framework for highly efficient selective gas adsorption

“…In the past two decades, porous MOFs materials, as a new type of advanced functional materials, have shown extensive applications in the fields of host–guest chemistry, 18–20 nonlinear optics, 21–23 catalysis, 24–27 magnetism, 28–30 gas storage and separation 31–39 due to their structural features such as high surface area, large pore volume, high density of open metal sites (OMSs), abundant Lewis base sites (LBSs), and the capability of functionalization and post-modification synthesis. Gas storage and separation is one of the most extensive research areas for MOFs materials, truly maximizing the advantages of pore structure design and reflecting the irreplaceable role of other inorganic materials.…”