Şavklıyıldız, İlyas2021-12-132021-12-1320210021-89791089-7550https://doi.org/10.1063/5.0043704https://hdl.handle.net/20.500.13091/1253Pressure and temperature dependences of the unit cell volumes of Y2O3's three polymorphs (cubic, monoclinic, and hexagonal) have been measured by synchrotron energy dispersive x-ray diffraction in conjunction with a cubic anvil technique to pressures and temperatures up to 7.5GPa and 1073K, respectively. The measured pressure-volume-temperature (P-V-T) data were used to obtain thermoelastic parameters of the polymorphs by fitting the modified high temperature third-order Birch-Murnaghan equation of state and a thermal pressure approach. The thermoelastic properties that were determined in this study are the ambient bulk modulus with fixed pressure derivative of the bulk modulus ( K 0 '</mml:msubsup> = 4.0 ), the isobaric temperature derivative of the bulk modulus ( partial derivative K / partial derivative T ) P, the volumetric thermal expansion coefficient along with the isothermal pressure derivative of thermal expansion ( partial derivative alpha / partial derivative P ) T, and the isometric temperature derivative of the bulk modulus ( partial derivative K / partial derivative T ) V. The ambient bulk modulus for cubic [152(7) GPa] and monoclinic [197(9) GPa] polymorphs agrees well with previous reports. There is no precedence for all other thermophysical properties of all three polymorphs of Y2O3 reported in this study. For instance, ( partial derivative K / partial derivative T ) P is the highest for the monoclinic polymorph, while ( partial derivative alpha / partial derivative P ) T and <mml:msub> ( partial derivative K / partial derivative T ) V are the highest for the cubic polymorph. The results of this study add to the stock of knowledge on the thermophysical properties of Y2O3, which is a technologically relevant solid state material.eninfo:eu-repo/semantics/closedAccessArticle10.1063/5.00437042-s2.0-85101743984