Get access

Orthorhombic In2O3: A Metastable Polymorph of Indium Sesquioxide


  • Financial support by the German Research Foundation within the priority programme SPP1236 and DESY are greatly acknowledged. The authors thank Christian Lathe for technical support and the Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, for the opportunity to perform experiments at the MAX200X press.


original image

The way is open for the physical and chemical characterization and single-crystal growth of the orthorhombic o′-In2O3 polymorph. Orthorhombic In2O3 is synthesized from rhombohedral corundum-type rh-In2O3 under moderately high-pressure and high-temperature conditions (8–9 GPa, 600–1100 °C) followed by recovery to ambient pressure and temperature. The crystal-structure data at ambient conditions confirm unambiguously the Rh2O3(II)-type structure.