Synthesis and Characterization of Single Crystal Samples of Spin-$1/2$   Kagome Lattice Antiferromagnets in the Zn-Paratacamite Family   Zn$_{x}$Cu$_{4-x}$(OH)$_{6}$Cl$_{2}$
  The Zn-paratacamite family, Zn$_{x}$Cu$_{4-x}$(OH)$_{6}$Cl$_{2}$ for $x \, \geq$ 0.33, is an ideal system for studying spin-1/2 frustrated magnetism in the form of antiferromagnetic Cu$^{2+}$ kagome planes. Here we report a new synthesis method by which high quality millimeter-sized single crystals of Zn-paratacamite have been produced. These crystals have been characterized by metal analysis, x-ray diffraction, neutron diffraction, and thermodynamic measurements. The $x$ = 1 member of the series displays a magnetic susceptibility that is slightly anisotropic at high temperatures with $\chi_{c} \, > \, \chi_{ab}$. Neutron and synchrotron x-ray diffraction experiments confirm the quality of these $x$ = 1 single crystals and indicate no obvious structural transition down to temperatures of T=2 K. 
Tianheng Han, Joel S. Helton, Shaoyan Chu, Andrea Prodi, Deepak K.   Singh, Claudio Mazzoli, Peter M\"uller, Daniel G. Nocer...
cond-mat.str-el cond-mat.mtrl-sci