X-ray diffraction study of pressure-induced amorphization in Lu2(WO4)3

The effect of pressure on the crystal structure of Lu2(WO4)3 has been studied up to 8.0 GPa using X-ray powder diffraction. The recovered samples showed that the diffracted intensity decreases as the pressure increases. The first evidence of amorphization occurs at ∼5.0 GPa and total amorphization is completed at 8.0 GPa. The bending of Lu–O–W bonds and the tilting of polyhedra in the framework structure are suggested as the mechanism of amorphization. The correlation of pressure-induced amorphization in materials that have a negative thermal expansion coefficient is further supported by structural and thermal expansion behavior in Lu2(WO4)3.