Electrically Conducting Organic Polymers: Connections Between Geometric and Electronic Structure

Electrically conducting organic polymers are relativity new materials with potential for many future elctronic applications. These materials exhibit a variety of unusual behaviour relative to conventional inorganic semiconductors. There are some important relationships between the geometric structure and the eletronic structure of the polymer chains, dependant at least in part upon their softness and 0ne-dimensional nature. Some of the well established connections between the electronic and chemical structures in the better known cinducting polymers are reviewed as an introduction to a discussion of the thermochromism discovered recently in certain of these aromatic polymes. The thermochromism results as a consequence of rotational defects in the geometric order of the polymer chains, which lead to cooresponding changes in the electronic structure which influence the optivcal properties of the material.