[Fe.sub.3]C cluster confined in single-walled carbon nanotubes: a first-principles study

First-principles calculations are used for studying the structures and magnetic and electronic properties of [Fe.sub.3]C cluster confined in various single-walled carbon nanotubes (SWCNT). The whole SWCNT + [Fe.sub.3]C system has exhibited a high spin polarization and has a potential use as spintronics devices with controllable structure and properties.