Abstract:
All four parameters of the Mie–Lennard-Jones pair interatomic potential have been determined, and the state equation $(P)$ and baric dependences of the lattice properties of an fcc iron are calculated using a previously proposed method. The dependences have been studied for the following properties: Debye temperature; the first, second, and third Gruneisen parameters; isothermal bulk modulus $B_T$ and $B'(P)$; isochoric specific heat $C_{p}$ and $C'_{v}(P)$; isobaric specific heat $C_p$; coefficient of thermal expansion $\alpha_{p}$ and $\alpha'_{p}(P)$; specific surface energy $\sigma$ and $\sigma'(P)$. Calculations performed along two isotherms (1500 and 3000 K) have shown good agreement with the experimental data. Analytical approximations of the baric dependences for $B'(P)$, $\alpha_{p}(P)$, $C_{p}(P)$, and $\sigma'(P)$ have been obtained, and it is shown that at $P\to\infty$ the functions $B_T(P)$ and $\sigma(P)$ change linearly, while the functions $\alpha'_{p}(P)$ and $C'_{p}(P)$ tend to zero. The calculated baric dependence of the melting temperature shows good agreement with the experimental data.