Synchrotron-based x-ray-diffraction study of the intermediate-high-pressure phase in the alloy In0.25Sn0.75 - art. no. 212104

In0.25Sn0.75 alloy stabilized in the primitive hexagonal phase at ambient c onditions is studied in a diamond anvil cell at high pressures with angle-d ispersive x-ray diffraction using the synchrotron radiation at ELETTRA. The ambient primitive hexagonal phase was found to undergo a reversible transf ormation to a mixture of body-centered-tetragonal and hexagonal-close-packe d phases above 11.6 GPa and not to the Cmca structure assigned in Si and Ge . The occurrence of the bct phase shows similarity to the high-pressure beh avior of Sn. A transformation mechanism from the ph to hcp phase via the bc t structure is also described.