Ferromagnetism in hexagonal close-packed Pd

We present theoretical and experimental data concerning the possibility of ferromagnetic order in bulk palladium. First principles, self-consistent DFT calculations including spin-orbit coupling performed at 0 K show that ferromagnetism occurs in bulk Pd at the optimum lattice constant if Pd is in a hexagonal close-packed (hcp) phase modification. In this phase Pd has, in comparison to Pd in its natural non-magnetic face-centred (fcc) structure, flatter bands at the Fermi level, fulfilling the Stoner criterion for ferromagnetism. We identify these bands in the bulk band structure and probe them with angle-resolved ultraviolet photo-electron spectroscopy in (11 0) oriented hexagonal close-packed Pd films deposited on W(100).