The band structures of polymers containing first row transition metal metallocenes were calculated using the one-dimensional tight-binding crystal orbital method along with the extended Huckel approximation. The metallocene polymers, except for ferrocene and chromocene polymers, possessed a partially occupied band. The ferrocene and chromocene polymers exhibit semiconductor character. Cobaltocene, nickelocene, and vanadocene polymers have a metallic character. The manganocene polymer has a partially occupied band that is localised. A change in the band structures of the metallocene polymers was compatible with an alternation of the energy levels of the 3d(z2) band of the transition metals. (c) 2007 Elsevier B.V. All rights reserved.