Néel and valence-bond crystal order on a distorted kagome lattice: Implications for Zn-paratacamite

Zn-paratacamite is a rare spin-1/2 antiferromagnetic insulator with an ideal kagome lattice structure in part of its phase diagram. As a function of Zn doping, this material undergoes a structural distortion which relieves the frustration and introduces magnetic order in the ground state, though the precise nature of the order is not clear at this point. In this paper, we present strong evidence for Néel ordering in the strongly distorted phase …