A Co(II)-based Molecular Magnet with a 6 T Coercive Field

TL;DR

This paper reports a Co(II)-based molecular magnet exhibiting an exceptionally high coercive field, attributed to strong exchange interactions along a one-dimensional chain, highlighting its potential as a hard magnetic material.

Contribution

It introduces a novel single-chain molecular magnet with a record coercive field, demonstrating the role of spin dynamics and exchange coupling in achieving high coercivity.

Findings

Achieved a large coercive field in a Co(II)-based molecular chain

Magnetic properties linked to strong exchange coupling and spin dynamics

Potential for designing high-performance molecular magnets

Abstract

Hard magnets with high coercivity, such as Nd2Fe14B and SmCo5 alloys, can maintain magnetisation under a high reverse external magnetic field and have therefore become irreplaceable parts in many practical applications. Molecular magnets are promising alternatives, owing to their precise and designable chemical structures, tuneable functionalities and controllable synthetic methods. Here, we demonstrate that an unusually large coercive field can be achieved in a single-chain magnet. Systematic characterisations, including magnetic susceptibility, heat capacity and neutron diffraction measurements, show that the observed giant coercive field originates from the spin dynamics along the one-dimensional chain of the compound because of the strong exchange coupling between Co(II) centres and radicals.