Possible valence-bond condensation in the frustrated cluster magnet LiZn2Mo3O8

TL;DR

This paper reports the synthesis of LiZn2Mo3O8, a frustrated antiferromagnet with magnetic moments on clusters, which may host an exotic valence-bond ground state, advancing understanding of cluster-based quantum states.

Contribution

It introduces a new cluster-based frustrated magnet that potentially exhibits a resonating valence-bond state, linking cluster magnetism to geometric frustration in solids.

Findings

LiZn2Mo3O8 shows signs of valence-bond condensation.

Magnetic moments are localized on transition metal clusters.

The material demonstrates a new approach for exploring emergent electronic states.

Abstract

The emergence of complex electronic behaviour from simple ingredients has resulted in the discovery of numerous states of matter. Many examples are found in systems exhibiting geometric magnetic frustration, which prevents simultaneous satisfaction of all magnetic interactions. This frustration gives rise to complex magnetic properties such as chiral spin structures orbitally-driven magnetism, spin-ice behavior exhibiting Dirac strings with magnetic monopoles, valence bond solids, and spin liquids. Here we report the synthesis and characterization of LiZn2Mo3O8, a geometrically frustrated antiferromagnet in which the magnetic moments are localized on small transition metal clusters rather than individual ions. By doing so, first order Jahn-Teller instabilities and orbital ordering are prevented, allowing the strongly interacting magnetic clusters in LiZn2Mo3O8 to probably give rise to an exotic condensed valence-bond ground state reminiscent of the proposed resonating valence bond state. Our results also link magnetism on clusters to geometric magnetic frustration in extended solids, demonstrating a new approach for unparalleled chemical control and tunability in the search for collective, emergent electronic states of matter.