Phase stability, electronic structure, and optical properties of indium oxide polytypes

Abstract

Structural phase stability, electronic structure, optical properties, and high-pressure behavior of polytypes of In 2 O 3 in three space group symmetry I2 1 3, Ia3 and R3 are studied by first-principles density functional calculations. From structural optimization studies lattice and positional parameters have been calculated, which are found to be in good agreement with the corresponding experimental data. In 2 O 3 of space group symmetry I2 1 3 and Ia3 are shown to undergo a pressureinduced phase transition to IO3 at pressures around 3.83 GPa. From analysis of band structure it is found that In 2 O 3 of space group symmetry I2 1 3 is indirect band gap semiconductors, while the other phase of space group Ia3 is direct band gap. The calculated carrier effective masses for all these three phases are compared with available experimental and theoretical values. From chargedensity and electron localization function analysis it is found that these phases have dominant ionic bonding. The magnitude of the absorption and reflection coefficients of In 2 O 3 with space group Ia3 and R3 are small in the energy range 0-5 eV, so that these materials can re regarded and classified as transparent.

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

“…Theoretical works in In 2 O 3 analyzed several structures and suggested the existence of the post-perovskite phase, 23,24 which, consequently, triggered considerable experimental efforts in order to find this phase at high pressures and high temperatures. [25][26][27][28][29] Noteworthy, experiments showed that the post-perovskite phase is not stable at high pressures in In 2 O 3 .…”

Engineering p – n junctions and bandgap tuning of InSe nanolayers by controlled oxidation

“…For the stable cubic (bixbyite) phase of In 2 O 3 , the primitive unit cell has a lattice parameter a = 10.077 Å (see figure 1(a)) [41]. In 2 O 3 has n-type conductivity due to the excess of In-atoms and oxygen vacancies, both of which act as donors.…”

Applications of Oxide Coatings in Photovoltaic Devices

“…Indium oxide In 2 O 3 crystallises in the bixbyite crystal structure with six fold coordination of the In 3+ ion and four fold coordination of the oxygen [31]. The valence band maximum is composed of O 2p states while the bottom of the conduction bands is made up of In 5s states [31].…”

“…The valence band maximum is composed of O 2p states while the bottom of the conduction bands is made up of In 5s states [31]. The O 2p states in the valence band are hybridized with In 4d core level states leading to an indirect band gap [32] in addition to a direct band gap of 3.2 eV.…”