In situhigh pressure high temperature experiments in multi-anvil assemblies with bixbyite-type In₂O₃and synthesis of corundum-type and orthorhombic In₂O₃polymorphs

Pbca-Type In2O3: The High-Pressure Post-Corundum phase at Room Temperature.

“…Curiously, our ab initio calculations (at T= 0K) indicate that o1-In 2 O 3 should be the most stable phase above 8 GPa (see Fig. 4) and below 36 GPa (α-Gd 2 S 3 type In 2 O 3 is the most stable one above this pressure in good agreement with previous calculations 26,36 ). The disagreement between experiments and calculations can be explained by the existence of a high kinetic energy barrier for the transformation from c-In 2 O 3 to o1-In 2 O 3 as already commented by several authors.…”

Synthesis and High-Pressure Study of Corundum-Type In2O3

“…42 All these phases are going to be named hereafter as c-In 2 O 3 , rh- The properties of the high-pressure phases of In 2 O 3 , some of which can be obtained in a metastable form at ambient conditions, are largely unknown despite their important applications. [37][38][39][40][41] In particular, a decrease on the bulk modulus is expected for the corundum-type structure of sesquioxides A 2 O 3 (A= Al, Ga, In) on increasing the cation ionic radius. In fact, Cr 3+ -doped Ga 2 O 3 was already postulated as a possible substitute of ruby (Cr 3+ -doped Al 2 O 3 ) for pressure sensor.…”

Structural and vibrational properties of corundum-type In2O3nanocrystals under compression

“…[45][46][47] In this respect, three additional orthorhombic phases of In2O3 have been theoretically predicted and indeed obtained by application of HP: Rh2O3-III type (SG Pbca, N. 61, Z= 8), 36,37 Rh2O3-II type (SG Pbcn, N. 60, Z= 4), 32,[48][49][50][51] and -Gd2S3-type (SG Pnma, N. 62, Z= 4). 52 Among them only the Pbcn phase has been claimed to be metastable at ambient conditions, [49][50][51] despite the Pbca phase is a phase reported at lower pressures than the Pbcn phase. 36,37 Working with nanocrystals opens the door to enhanced properties of materials; 53,54 and adds the possibility of obtaining metastable HP crystalline and amorphous phases at room conditions with different properties from the original material.…”