Confirmation of Long-Range Magnetic Order in CuSb2O6

The presence of long-range order in CuSb2O6 was confirmed by low-temperature neutron diffraction data. A magnetic super-lattice reflection was indexed with the wavevector k = (12, 0, 12). This propagation vector is identical to that of CoSb2O6. The extremely weak intensity of the magnetic reflection prevented the analysis of the neutron data by Rietveld refinement, but instead the magnetic moment was obtained by simulating the diffraction pattern while varying the magnetic moment of Cu2+. A moment value of 0.5 μB is believed to be the best approximation for the actual moment at 5 K. Further evidence for the presence of the ordered state is obtained from a spin-flop phase transition which occurred at 2.2 T at 5 K in a single crystal.