Study of Grüneisen parameter and Debye temperature for hcp-iron under high pressure

We have derived the expression Debye temperature for hcp-iron using the volume dependence Grüneisen parameter γ(V)=γ0[1+a{(VV0)b−1}], where a and b are volume independent adjustable parameters. Using the formulation of γ, we have determined the expressions for the second-order Grüneisen parameter, Debye temperature and the shear velocity for hcp-iron. However, even though the Grüneisen parameter and the equation of state (EOS) are directly connected, it is often the case that individual forms of γ and the EOS can selected independently. Therefore, the equation of state, Bulk modulus and its first derivative of bulk modulus have been also determined for hcp-iron using the Eulerian finite theory which is based on n-th power of edge length by compression recently reported by Singh et al. We have calculated the Grüneisen parameter, second-order Grüneisen parameter, Debye temperature and the shear velocity for hcp-iron in order to test the applicability of the present formulation. The obtained results are very close and compatible with experimental data.