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Equation of State of Liquid Iron under Extreme Conditions
Yasuhiro Kuwayama1,2, Guillaume Morard3,4, Yoichi Nakajima5,6
1Department of Earth and Planetary Science, The University of Tokyo, 113-0033 Tokyo, Japan.
Abstract:
The density of liquid iron has been determined up to 116 GPa and 4350 K via static compression experiments following an innovative analysis of diffuse scattering from liquid. The longitudinal sound velocity was also obtained to 45 GPa and 2700 K based on inelastic x-ray scattering measurements. Combining these results with previous shock-wave data, we determine a thermal equation of state for liquid iron. It indicates that Earth's outer core exhibits 7.5%-7.6% density deficit, 3.7%-4.4% velocity excess, and an almost identical adiabatic bulk modulus, with respect to liquid iron.
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