Pressure–volume–temperature equation of state of ε–FeOOH to 11 GPa and 700 K

Abstract

A new synchrotron X–ray diffraction study of ε–FeOOH has been carried out to determine the pressure–volume–temperature (P–V–T) equation of state (EOS). The P–V–T data fitted a third–order Birch–Murnaghan EOS yielded: isothermal bulk modulus K_T0 of 135(3) GPa; its pressure derivative K′ of 6.1(9); (∂K_T/∂T)_P of −0.05(2) GPa K⁻¹; a₀ of 2.6(7) × 10⁻⁵ K⁻¹ and a₁ of 1.0(3) × 10⁻⁷ K⁻², where the volumetric thermal expansion coefficient is described as α_0,T = a₀ + a₁ × (T − 300).