Isothermal compressibility and anisotropic structural response of As2O5 under pressure

The isothermal compressibility of As2O5 has been studied up to a pressure of 19.5 GPa. High resolution X-ray powder diffraction and a membrane driven diamond anvil cell were used to determine the bulk moduli and their pressure derivatives according to various Equations of States and to investigate a potential transformation to a high pressure polymorph. A mechanism which inhibits such a phase transformation up to the maximum applied pressure was revealed.