| Summary: | Polar magnetic materials exhibiting appreciable asymmetric exchange interactions can potentially host new topological states of matter such as vortex-like spin textures; however, realizations have been mostly limited to half-integer spins due to rare numbers of integer spin systems with broken spatial inversion lattice symmetries. Here, we studied the structure and magnetic properties of the <i>S</i> = 1 integer spin polar magnet β-Ni(IO<sub>3</sub>)<sub>2</sub> (Ni<sup>2+</sup>, d<sup>8</sup>, <sup>3</sup>F). We synthesized single crystals and bulk polycrystalline samples of β-Ni(IO<sub>3</sub>)<sub>2</sub> by combining low-temperature chemistry techniques and thermal analysis and characterized its crystal structure and physical properties. Single crystal X-ray and powder X-ray diffraction measurements demonstrated that β-Ni(IO<sub>3</sub>)<sub>2</sub> crystallizes in the noncentrosymmetric polar monoclinic structure with space group <i>P</i>2<sub>1</sub>. The combination of the macroscopic electric polarization driven by the coalignment of the (IO<sub>3</sub>)<sup>−</sup> trigonal pyramids along the <i>b</i> axis and the <i>S</i> = 1 state of the Ni<sup>2+</sup> cation was chosen to investigate integer spin and lattice dynamics in magnetism. The effective magnetic moment of Ni<sup>2+</sup> was extracted from magnetization measurements to be 3.2(1) µ<sub>B</sub>, confirming the <i>S</i> = 1 integer spin state of Ni<sup>2+</sup> with some orbital contribution. β-Ni(IO<sub>3</sub>)<sub>2</sub> undergoes a magnetic ordering at <i>T</i> = 3 K at a low magnetic field, <i>μ</i><sub>0</sub><i>H</i> = 0.1 T; the phase transition, nevertheless, is suppressed at a higher field, <i>μ</i><sub>0</sub><i>H</i> = 3 T. An anomaly resembling a phase transition is observed at <i>T</i> ≈ 2.7 K in the C<sub>p</sub>/<i>T</i> vs. <i>T</i> plot, which is the approximate temperature of the magnetic phase transition of the material, indicating that the transition is magnetically driven. This work offers a useful route for exploring integer spin noncentrosymmetric materials, broadening the phase space of polar magnet candidates, which can harbor new topological spin physics.
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