Thermodynamic properties of bcc iron at extreme compression
S. K. Srivastava, Pallavi Sinha and Nidhi Verma
An expression for volume dependence of the Grüneisen ratio is introduced. Such expression is used to estimate the various thermodynamic properties of bcc iron, main element of the Earth’s inner core. Dependable values of volume dependence of γ, q, λ and θ are predicted. In high temperature region, entropy, thermal energy and product aKT are found to change linearly with the change in volume but these properties become non-linear in very high compression region (η < 0.5). Alternative phenomenological and empirical expressions are suggested to better understand the properties of bcc iron at inner core pressure.
Keywords: bcc iron; Gruneisen ratio; equations of state.