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DOE OSTI · 1907826

Layered polymorph of titanium triiodide

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

A previously unreported layered spin ½ triangular lattice polymorph of TiI 3 is described, synthesized under 6 GPa of applied pressure at 900 °C, but stable at atmospheric pressure. This air-sensitive material has a CdI 2 -type layered structure (P-3m1 (no. 164), a = 4.012 Å and c = 6.641 Å at 120 K, Z = 1 of Ti 0.667 I 2 ) with an in-plane triangular lattice, related to that of TiI 4 (Ti 0.5 I 2 ). Although the TiI 3 formula is consistent with expectations for a layered honeycomb lattice of spin ½ 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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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYTitanium triiodidehigh pressure synthesislayered structurepolymorphismspin 1/2

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Ni, Danrui, Mudiyanselage, Ranuri S. Dissanayaka, Xu, Xianghan, Mun, Junsik, Zhu, Yimei, Xie, Weiwei, Cava, R. J.. 2022-12-01. Layered polymorph of titanium triiodide. https://doi.org/10.1103/physrevmaterials.6.124001

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