Enhanced incompressibility in iron doped nano particles of indium sesquioxide under high pressure

Angle dispersive x-ray diffraction studies were carried out on nano particles of iron doped indium oxide upto pressures of 52 GPa. Our studies show that it undergoes a reversible phase transition to the rhombohedral corrundum phase at ∼ 30 GPa. However, the diffraction peaks of the released phase are very broad and are overriding on a large background. This indicates that there is some disorder in the indium oxide lattice on release of pressure. The bulk modulus of the initial cubic phase was determined to be 186 GPa. It was observed that beyond 20 GPa the lattice of iron doped indium oxide became very incompressible with an average compressibility of 0.16 % compared to ∼ 0.5 % for the initial phase. This may be attributed to iron doping.