Electronic structures of organometallic polymers containing μ2-bridging pentalene and indacene ligands

Band structures of organometallic polymers containing μ2-bridging pentalene or indacene ligands for the transition metals have been calculated by using the tight-binding crystal orbital method. Polymers containing pentalene and s-indacene with iron atoms possess small band gaps with broad bands near the Fermi level. On the other hand, polymers containing cobalt or nickel atoms exhibit a metallic or semi-metallic character, which suggests the possibility of changes in their structures. We have analysed the crystal orbital phases to examine the electronic structures.