Pressure-induced phase transitions of HgSe

Pressure-induced phase transitions of mercury selenide were studied by energy-dispersive x-ray diffraction methods using the Cornell High Energy Synchrotron Source. Phase III was determined to be a sodium chloride crystal structure. At 280 kbar, this phase began to transform to phase IV, which may be indexed as an orthorhombic crystal structure. The percentage volume decrease of this phase transition was found to be 8.3% at 305 kbar, where both phases were present.