The electronic structures of ferrocene-containing polymers with heteroatom-bridges have been examined using the tight-binding crystal orbital method. The relationship between the band structures of the polymers and their bridging moieties was examined. The highest occupied (HO) band of the polymers with saturated carbon-bridges consisted of pi-type p orbitals of cyclopentadienyl ring. On the other hand, the polymers with silicon-bridges possessed a localised HO band, which was formed by 3d(z)(2) orbitals of iron atom. (c) 2007 Elsevier B.V. All rights reserved.