Magnetic order and spin liquid behavior in [Mo3]11+ molecular magnets

Molecular magnets with one unpaired electron per molecule offer promise in the ongoing search for exotic states of matter, including quantum spin liquids. Here, the authors investigate a series of molecular magnets based on Mo trimer building blocks with one unpaired electron each and find that the magnetic ground states are very sensitive to small changes in the breathing parameter---the ratio between first and second nearest neighbor bond lengths in the breathing kagome lattice that they form. When this parameter is sufficiently close to 1, these materials show an absence of magnetic order and other hallmarks of quantum spin liquid behavior, which may be correlated with plaquette charge ordering.