DFT calculations of iron-carbides using the FPLAPW method

Density functional theory calculations of the structural, energetic, electronic and magnetic properties of iron-carbides using the GGA approach are presented. Fe₁₆C, η -Fe₂C and Fe₂C carbides with carbons occupying different octahedral site are studied. Software WIEN2K with PBE-96 exchange correlation functional was used. Bulk modulus by mean Birch-Murnaghan state equation was determined for each structure. Band structure, relief and contour maps of total and partial DOS was evaluated showing predominance of Fe 3d orbital for energies around the Fermi level. All the crystals have ferromagnetic ground state, and martensite and η-Fe₂C are energetically most favored than other Fe₂C carbides. The position change of octahedral C affects the energetic stability and the magnetization of Fe₂C carbides.