Electrochemical Control of Magnetism on the Breathing Kagome Network of Li x ScMo3O8

Controlling properties within a given functional inorganicmaterialstructure type is often accomplished through tuning the electronicoccupation, which is in turn dictated by the elemental compositiondetermined at the time of material preparation. We employ electrochemicalcontrol of the lithium content, with associated electronic occupancycontrol, to vary the magnetic properties of a material where a kagome-derivednetwork of Mo-3 triangles carry the spin. In this case,Li is electrochemically inserted into LiScMo3O8, a layered compound containing a breathing Mo kagome network. Upto two additional Li can be inserted into LiScMo3O8, transforming it into Li3ScMo3O8. Li2ScMo3O8 prepared byelectrochemical lithiation is compared to the quantum spin liquidcandidate compound Li2ScMo3O8 preparedthrough high-temperature solid-state methods, which has a slightlydifferent structural stacking sequence but a similar kagome-derivednetwork. Magnetic measurements are supported by first-principles calculations,showing that electrons remain localized on the Mo clusters throughoutthe doping series. As x is varied in Li x ScMo3O8, the measurements andcalculations reveal the evolution from a diamagnetic band insulatorat x = 1 to a geometrically frustrated magnet at x = 2, back to a diamagnetic insulator at x = 3. These results indicate a likelihood of strong coupling betweenthe degree of Li disorder and charge/magnetic ordering over the Mo-3 clusters.

Automated summary

Controlling the magnetic properties of functional inorganic materials with a kagome-derived network is achieved by electrochemically controlling the lithium content. The electronic occupancy and consequent magnetic properties are varied by inserting up to two additional lithium ions into LiScMo3O8. The measurements and calculations reveal the evolution from a diamagnetic band insulator to a geometrically frustrated magnet and back to a diamagnetic insulator as the lithium content changes.