On the electronic structure of carbon in α-iron

Abstract

The electronic structure of carbon atom in a ferromagnetic transition metal is computed in a Hartree-Fock scheme, taking full account of the Friedel sum rule. The atomic ‘p’ levels of the carbon atom are expected to fall within the ‘d’ part of the band structure of the transition metal. It appears possible to screen the additional charge arising from the carbon atom without perturbing potentials on the neighbouring crystal sites of the carbon but these results are not completely consistent with the available experimental results. Taking into account an extended perturbation up to second-nearest neighbours, reasonable agreement with saturation magnetization and hyperfine fields can be obtained.