A cluster calculation of the muon hyperfine field in nickel

The authors have performed a partially self-consistent, first-principles calculation of the hyperfine field at a μ+ at the octahedral interstitial site in ferromagnetic nickel. Various calculations were performed of the spin-dependent charge density in the central region of a spherically averaged superposition of atomic charge densities. In this way it was found that: (1) The electronic configuration of bulk Ni contains a significant amount of 4p-states, in agreement with other calculations. (2) The μ+ produces only a weak perturbation on its nearest-neighbor Ni atoms. (3) The hyperfine field at the μ+ is opposite to the bulk magnetization and has the value -590 G, in good agreement with the measured value of -641 G. (Auth.)