High-Pressure oC16-YBr3 Polymorph Recoverable to Ambient Conditions - From 3D Framework to Layered Material
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2024-07-02 |
| Journal | Inorganic Chemistry |
| Authors | Alena AslandukovŠ°, Andrey Aslandukov, Fariia Iasmin Akbar, Yuqing Yin, Florian Trybel |
| Institutions | University of Bayreuth, University of Chicago |
Abstract
Section titled āAbstractāExfoliation of graphite and the discovery of the unique properties of grapheneāgraphiteās single layerāhave raised significant attention to layered compounds as potential precursors to 2D materials with applications in optoelectronics, spintronics, sensors, and solar cells. In this work, a new orthorhombic polymorph of yttrium bromide, <i>oC</i>16-YBr<sub>3</sub> was synthesized from yttrium and CBr<sub>4</sub> in a laser-heated diamond anvil cell at 45 GPa and 3000 K. The structure of <i>oC</i>16-YBr<sub>3</sub> was solved and refined using in situ synchrotron single-crystal X-ray diffraction. At high pressure, it can be described as a 3D framework of YBr<sub>9</sub> polyhedra, but upon decompression below 15 GPa, the structure motif changes to layered, with layers comprising edge-sharing YBr<sub>8</sub> polyhedra weakly bonded by van der Waals interactions. The layered <i>oC</i>16-YBr<sub>3</sub> material can be recovered to ambient conditions, and according to Perdew-Burke-Ernzerhof-density functional theory calculations, it exhibits semiconductor properties with a band gap that is highly sensitive to pressure. This polymorph possesses a low exfoliation energy of 0.30 J/m<sup>2</sup>. Our results expand the list of layered trivalent rare-earth metal halides and provide insights into how high pressure alters their structural motifs and physical properties.