Electronic structure of the ferromagnetic superconductor UCoGe from first principles

The superconductor UCoGe is analysed with electronic structure calculations using a linearized augmented plane wave method based on density functional theory. Ferromagnetic and antiferromagnetic calculations with and without correlations ( via LDA + U(H)) were done. In this compound the Fermi level is situated in a region where the main contribution to DOS comes from the U-5f orbital. The magnetic moment is mainly due to the Co-3d orbital with a small contribution from the U-5f orbital. The possibility of fully non-collinear magnetism in this compound seems to be ruled out. These results are compared with the isostructural compound URhGe; in this case the magnetism comes mostly from the U-5f orbital.