Invertis Journals of Science & Technology

S. G. Khambholja ¹, B. Y. Thakore ², A. R. Jani ²

Affiliations
1 Department of Science & Humanities, B.&B. Institute of Technology, Vallabh Vidyanagar, Gujarat, IN
2 Department of Physics, Sardar Patel University, Vallabh Vidyanagar, Gujarat, IN

Abstract

Iron Carbide exist in earth's lower mantle and it crystallize in various crystallographic structure depending upon the thermodynamic conditions. The thermodynamic state of lower earth region are quite complicated due to simultaneous effect of pressure and/or temperature. In such a situation the study of pressure dependent properties of FeC is important. In the present paper, we report the structural properties of FeC using first principles calculations. The structural properties are studied at various pressures in order to determine the high pressure behavior of this carbide in rock salt structure. The computed properties agree well with the previously reported results. One of the most important properties of the material is the pressure induced structural phase transition from one phase to another. In the present study, we do not observe any structural phase transition from rock salt structured FeC to CsCl structured FeC up to 100 GPa. The present results are also useful as FeC is refractory carbide, a material of great technological importance at non ambient conditions.

Keywords

Structural Properties, Density Functional Theory.

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A. B. Patel ¹, N. K. Bhatt ², B. Y. Thakore ²

Affiliations
1 Department of Physics, School of Sciences, Gujarat University, Ahmedabad, Gujarat-380009, IN
2 Department of Physics, Sardar Patel University, Vallabh Vidyanagar, Gujarat-388120, IN

Abstract

The electrical resistivity of metallic liquid Gallium has been calculated at different temperatures using the self-consistent approach. Most celebrated Ziman formula does not take account the blurring effect of the Fermi surface at high temperatures. So, our purpose has been to show that the self-consistent resistivity formula with temperature dependent pair potential, which takes account of blurring effect, gives better results than the simple Ziman equation under the same assumptions. As the input pseudopotential, the potential proposed by Hasegawa et al was used for full electronion interaction, which is valid for all electrons. To evaluate the temperature dependence of structure factor is described by temperature dependent potential parameter in the pair potential. Finally, the calculation of the thermal conductivity and thermo-electric power is straight forward. Same trend of resistivity with experimental data is observed, which confirms the proposed scheme for fitting the potential parameter.

Keywords

Electrical Resistivity, Thermo-Electric Power, Pseudopotential, Ga.

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