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arXiv · 2210.00097

A Layered Spin 1/2 polymorph of titanium triiodide

Danrui Ni·Ranuri S. Dissanayaka Mudiyanselage·Xianghan Xu·Junsik Mun·Yimei Zhu·Weiwei Xie·R. J. Cava
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Abstract

A previously unreported layered spin 1/2 triangular lattice polymorph of TiI3 is described, synthesized under 6 GPa of applied pressure at 900 C, but stable at atmospheric pressure. This air-sensitive material has a CdI2-type layered structure (P-3m1 (#164), a = 4.012 A and c = 6.641 A at 120 K, Z = 1 of Ti0.667I2) with an in-plane triangular lattice, related to that of TiI4 (Ti0.5I2). Although the TiI3 formula is consistent with expectations for a layered honeycomb lattice of spin 1/2 Ti(III), there appears to be disorder in the crystal structure. Magnetic susceptibility and heat capacity measurements suggest that the material undergoes several low temperature phase transitions.

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Danrui Ni, Ranuri S. Dissanayaka Mudiyanselage, Xianghan Xu, Junsik Mun, Yimei Zhu, Weiwei Xie, R. J. Cava. 2022-09-30. A Layered Spin 1/2 polymorph of titanium triiodide. https://doi.org/10.1103/physrevmaterials.6.124001

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