Search

Magnetization measurements on single-crystal cubic $\mathrm{Sr}\mathrm{Cu}{\mathrm{Te}}_{2}{\mathrm{O}}_{6}$ with an applied magnetic field along three inequivalent high symmetry directions [100], [110], and [111] reveal weak magnetic anisotropy. The fits of the magnetic susceptibility to the result from a quantum Monte Carlo simulation on the Heisenberg spin-chain model, where the chain is formed via the dominant third-nearest-neighbor exchange interaction ${J}_{3}$, yield the intrachain interaction $({J}_{3}/{k}_{B})$ between 50.12(7) K for the applied field along [110] and 52.5(2) K along [100] with about the same $g$ factor of 2.2. Single-crystal neutron diffraction unveils the transition to the magnetic ordered state as evidenced by the onset of the magnetic Bragg intensity at ${T}_{\text{N1}}=5.25(9)\phantom{\rule{0.16em}{0ex}}\mathrm{K}$ with no anomaly of the second transition at ${T}_{\text{N2}}$ reported previously. Based on irreducible representation theory and magnetic space group analysis of powder and single-crystal neutron diffraction data, the magnetic structure in the Shubnikov space group $P{4}_{1}32$, where the ${\mathrm{Cu}}^{2+}\phantom{\rule{4pt}{0ex}}S=1/2$ spins antiferromagnetically align in the direction perpendicular to the spin chain, is proposed. The measured ordered moment of $0.52(6)\phantom{\rule{0.16em}{0ex}}{\ensuremath{\mu}}_{B}$, which represents 48% reduction from the expected value of $1\phantom{\rule{0.16em}{0ex}}{\ensuremath{\mu}}_{B}$, suggests the remaining influence of frustration resulting from the ${J}_{1}$ and ${J}_{2}$ bonds.

High-resolution time-of-flight powder neutron diffraction and high-field magnetization were measured to investigate the magnetic structure and existence of a field-induced magnetic phase transition in the distorted kagome antiferromagnet ${\mathrm{Cs}}_{2}{\mathrm{Cu}}_{3}{\mathrm{SnF}}_{12}$. Upon cooling from room temperature, the compound undergoes a structural phase transition at ${T}_{\mathrm{t}}=185\phantom{\rule{0.28em}{0ex}}\mathrm{K}$ from the rhombohedral space-group $R\overline{3}m$ with the perfect kagome spin network to the monoclinic space-group $P{2}_{1}/n$ with the distorted kagome planes. The distortion results in three inequivalent exchange interactions among the $S=1/2\phantom{\rule{0.28em}{0ex}}{\mathrm{Cu}}^{2+}$ spins that magnetically order below ${T}_{\mathrm{N}}=20.2\phantom{\rule{0.28em}{0ex}}\mathrm{K}$. Magnetization measured with a magnetic field applied within the kagome plane reveals small in-plane ferromagnetism resulting from spin canting. On the other hand, the out-of-plane magnetization does not show a clear hysteresis loop of the ferromagnetic component nor a prominent anomaly up to 170 T with the exception of the subtle kneelike bend around 90 T, which could indicate the 1/3 magnetization plateau. The combined analysis using the irreducible representations of the magnetic space groups and magnetic structure refinement on the neutron powder-diffraction data suggests that the magnetic moments order in the magnetic space-group $P{2}_{1}^{\ensuremath{'}}/{n}^{\ensuremath{'}}$ with the all-in--all-out spin structure, which by symmetry allows for the in-plane canting, consistent with the in-plane ferromagnetism observed in the magnetization.

We revisited the crystal structure of α-Cu2V2O7. An absolute structure determination have been performed. Ten pieces of crystals were randomly selected from a single large crystal. Inclusion of inv...