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arXiv · 1710.04889

Low-dimensional quantum magnetism in Cu(NCS)$_2$: A molecular framework material

Matthew J. Cliffe·Jeongjae Lee·Joseph A. M. Paddison·Sam Schott·Paromita Mukherjee·Michael W. Gaultois·Pascal Manuel·Henning Sirringhaus·Siân E. Dutton·Clare P. Grey
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Abstract

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.

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Matthew J. Cliffe, Jeongjae Lee, Joseph A. M. Paddison, Sam Schott, Paromita Mukherjee, Michael W. Gaultois, Pascal Manuel, Henning Sirringhaus, Siân E. Dutton, Clare P. Grey. 2017-10-13. Low-dimensional quantum magnetism in Cu(NCS)$_2$: A molecular framework material. https://doi.org/10.1103/physrevb.97.144421

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