Structural investigation of antisite-disordered FeGa3 under high-pressure.

We investigate the crystal structure stability of the cage compound FeGa₃ in the presence of Fe antisite disorder (namely as Fe0.258Ga0.742) using room-temperature x-ray diffraction (XRD) as a function of pressure up to 38 GPa. Our results show a crystal structure instability, with the emergence of a second crystallographic phase of different symmetry at a critical pressure in the range of P_c ≈ 16 - 18 GPa, similar to what was previously reported for pristine FeGa₃. Our results are a first step in understanding the effect of pressure in the crystal structure of FeGa₃ in the presence of disorder. [ABSTRACT FROM AUTHOR]