Magnetism and electronic structure of Fe chains and nano-wires

The electronic and magnetic structures of an Fe linear chain and FCC and BCC nano-wires were determined by accurate first-principles self-consistent full potential linearized augmented plane wave calculations. The one-dimensional nature of the systems results in dramatic changes in their properties - as expected from the early predictions of Weinert and Freeman (J. Mag. Magn. Mater. 38 (1983) 23) for linear transition metal chains: a high density of states arising from van Hove singularities, large s-d-exchange splittings (larger in the chain than in the wires) and filled majority d bands (i.e., a "strong Stoner" ferromagnet) and strikingly enhanced Fe magnetic moments that depend on their coordination number. These unusual and distinctive properties are expected to invite somewhat unique experimental characterizations.