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The present manuscript reports high-pressure investigations on nano-crystalline Scandium Oxide (Sc2O3) through synchrotron angle dispersive x-ray diffraction technique (ADXRD) up to a pressure of ∼35.4 GPa using a diamond-anvil cell (DAC). The sample, having a cubic bixbyite structure at ambient conditions, underwent substantial changes in crystallographic parameters under the application of external pressure, while exhibiting phase stability i.e. does not undergo any structural phase transition up to 35.4 GPa. The lattice parameters and the unit cell volume decrease significantly with an increase in pressure, revealing the compressible nature of the crystal structure. The pressure-volume data is fitted using the third-order Birch-Murnaghan equation of state to calculate the bulk modulus and its first derivative, which yields zero pressure bulk modulus of 217(35) GPa, with B 0 ′ = 12(4) and the corresponding ambient volume per unit molecule comes out to be 59.18(18) Å3.

The pressure dependent structural properties of polycrystalline Mn2−xCrxO3 (x = 0, 0.01, 0.05) multiferroics have been investigated using synchrotron x-ray diffraction (SXRD) measurements up to 41 GPa at room temperature (RT). Our results illustrate that irrespective of their RT crystal structure, all the studied samples undergo pressure induced structural phase transition to monoclinic phase. For pristine Mn2O3, the phase transition starts around 20.8 GPa and completely transformed to monoclinic phase around 37 GPa during compression. The co-existence of orthorhombic and monoclinic phase persists at wide pressure range i.e. 20.8 to 37 GPa. The Cr substitutions lower the required pressure for pressure induced phase transition i.e. for x = 0.01 and x = 0.05, Cr doped samples, the pressure induced phase transition occurs at 35 GPa and 33 GPa, respectively. These transitions are reversible (with hysteresis) during decompression and remained unquenchable under pressure. These results corroborate that Cr substitution modify the RT crystal structure and induces positive chemical pressure in Mn2O3.

Temperature-dependent structural studies of polycrystalline Bi1−x Sb x alloys were carried out using synchrotron x-ray diffraction. In-depth powder diffraction analysis reveals that an iso-structural phase transition takes place in the rhombohedral Bi-Sb alloy around 200 K, which is accompanied by anomalous behavior in the temperature-dependent linear thermal expansion data. In addition, the thermal variation of refined isotropic thermal parameters or Debye-Waller factor (B iso), ratio of the lattice parameters and Debye temperature indicates that anisotropy, arising due to local structural disorder, plays a significant role in this material.