An Energy-Dispersive X-Ray Diffraction Study of Monoclinic Eu2O3 under Pressure

The phase behavior of monoclinic (B-type) Eu2O3 under pressure in a diamond anvil cell was studied at room temperature by energy-dispersive X-ray diffraction at the Cornell High Energy Synchrotron Source. The bulk modulus (B0) of B-type Eu2O3, derived from the compression curve obtained, was 140 GPa. A pressure-induced phase transition from the monoclinic to the hexagonal (A-type) crystal structure was observed at about 4.7 GPa. The fractional volume change, ΔV/V, under this transition pressure was approximately -2%.