Disorder-Induced Structural Complexity in the Barlowite Family of S = 1/2 Kagome Magnets

摘要

We present a comprehensive structural and magnetic characterization of the barlowite family of S = 1/2 kagome magnets, Cu4(OH)6FX, where X = Cl, Br, or I. Through high-resolution synchrotron X-ray and neutron powder diffraction measurements, we reveal two sources of structural complexity within this family of materials, namely, compositional disorder of the halide species that occupy sites in between the kagome layers and the positional disorder of the interlayer Cu~(2+) ions that persists well into the Pnma structural ground state. We demonstrate that understanding these inherent structural disorders is key as they correlate with the degree of partial order in the magnetic ground states of these quantum frustrated magnets.