Electronic Structure of Conjugated Polymers: Consequences of Electron}lattice Coupling

Conjugated organic polymers can be doped, via oxidation or reduction chemistry or via acid}base chemistry, to induce very high electrical conductivity. Conjugated polymers are beginning to "nd uses, in both the neutral and the doped states, in prototype molecular-based electronics applications and in electronic and opto-electronic devices. The physical basis for the many of the unusual properties of these new materials is discussed, at a su$cient level of approximation to enable an understanding of the important issues by the general condensed matter physicist. In particular, emphasis is placed on the interconnections of the electronic, geometric and chemical structures, in the ground state and especially in the excited states. The important role of electron}electron and electron}lattice interactions are pointed out, and justi"ed through a combined experimental}theoretical approach. ( 1999 Elsevier Science B.V. All rights reserved. PACS: 71.20.Rv; 36.20.Kd; 42.70.Jk