Giant Antiferromagnetically Coupled Moments in a Molecule-Based Magnet with Interpenetrating Lattices

TL;DR

This study reveals that a molecule-based magnet with interpenetrating lattices exhibits giant antiferromagnetically coupled moments, showing unique magnetic behavior with high coercivity and remanence, differing from typical metamagnetic materials.

Contribution

It demonstrates that the material behaves as two giant moments with weak antiferromagnetic coupling and large energy barriers, providing new insights into its magnetic properties.

Findings

Displays a metamagnetic transition with substantial remanence and coercivity.

Acts like two weakly-coupled giant magnetic moments.

Magnetic correlation length can be estimated from magnetization.

Abstract

The molecule-based magnet [Ru$_2$(O$_2$CMe)$_4$]$_3$[Cr(CN)$_6$] contains two weakly-coupled, interpenetrating sublattices in a body-centered cubic structure. Although the field-dependent magnetization indicates a metamagnetic transition from an antiferromagnet to a paramagnet, the hysteresis loop also exhibits a substantial magnetic remanance and coercive field uncharacteristic of a typical metamagnet. We demonstrate that this material behaves like two giant moments with a weak antiferromagnetic coupling and a large energy barrier between the orientations of each moment. Because the sublattice moments only weakly depend on field in the transition region, the magnetic correlation length can be directly estimated from the magnetization.