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Low-dimensional magnetic materials with spin-$frac{1}{2}$ moments can host a range of exotic magnetic phenomena due to the intrinsic importance of quantum fluctuations to their behavior. Here, we report the structure, magnetic structure and magnetic properties of copper(II) thiocyanate, Cu(NCS)$_2$, a one-dimensional coordination polymer which displays low-dimensional quantum magnetism. Magnetic susceptibility, electron paramagnetic resonance (EPR) spectroscopy, $^{13}$C magic-angle spinning nuclear magnetic resonance (MASNMR) spectroscopy, and density functional theory (DFT) investigations indicate that Cu(NCS)$_2$ behaves as a two-dimensional array of weakly coupled antiferromagnetic spin chains ($J_2 = 133(1)$ K, $alpha = J_1/J_2 = 0.08$). Powder neutron-diffraction measurements confirm that Cu(NCS)$_2$ orders as a commensurate antiferromagnet below $T_mathrm{N} = 12$ K, with a strongly reduced ordered moment (0.3 $mu_mathrm{B}$) due to quantum fluctuations.
Inelastic neutron scattering for temperatures below 30 K from a powder of LiZn2Mo3O8 demonstrates this triangular-lattice antiferromagnet hosts collective magnetic excitations from spin 1/2 Mo3O13 molecules. Apparently gapless (Delta < 0.2 meV) and e
We report $alpha$-Cu$_2$V$_2$O$_7$ to be an improper multiferroic with the simultaneous development of electric polarization and magnetization below $T_C$ = 35 K. The observed spontaneous polarization of magnitude 0.55 $mu$Ccm$^{-2}$ is highest among
Single crystals of the layered organic type II superconductor, $kappa$-(BEDT-TTF)$_{2}$Cu(NCS)$_{2}$, have been studied in magnetic fields of up to 33 T and at temperatures between 0.5 K and 11 K using a compact differential susceptometer. When the m
We report detailed neutron scattering studies on Ba$_2$Cu$_3$O$_4$Cl$_2$. The compound consists of two interpenetrating sublattices of Cu, labeled as Cu$_{rm A}$ and Cu$_{rm B}$, each of which forms a square-lattice Heisenberg antiferromagnet. The tw
Kitaev quantum spin liquids (QSLs) are exotic states of matter that are predicted to host Majorana fermions and gauge flux excitations. However, so far all known Kitaev QSL candidates are known to have appreciable non-Kitaev interactions that pushes