Mean field potential approach to study thermodynamic properties of bcc iron
Priyank Kumar, N. K. Bhatt, P. R. Vyas and V. B. Gohel
Theoretical calculations of thermodynamic properties of bcc iron (Fe) have been carried out systematically using mean field potential (MFP) approach in conjunction with local pseudopotential at extreme environment. We have analyzed static energy and lattice constant, temperature variations of Helmholtz free energy, free energy due to lattice ions, thermal expansion, enthalpy, specific heats at constant volume and pressure, specific heat due to lattice ions and thermally excited electrons, isothermal and adiabatic bulk moduli and thermodynamic Gruneisen parameter. Static and dynamic equations of state along with temperature along principle Hugoniot are also reported. Present results are found to be in good agreement with experimental and other theoretical results. Good accordance of presently obtained results with other reported results confirms that the presently used conjunction scheme (MFP + pseudopotential) accounts anharmonic effects at high temperature properly along with its computational simplicity, physical transparency and reliability. Pseudopotential method can be used successfully for the study of thermodynamic properties of transition metals at extreme environment which accounts pressure induced s to d transfer of electrons.
Keywords: Thermophysical properties, bcc structure, iron, transition metals, mean field potential, pseudopotential, anharmonic effect