Electroactive and photochromic molecular materials for wires, switches and memories

Properties of synthetic electroactive and photochromic molecular systems are described, with particular emphasis on microscopic processes controlling these properties. Both low-molecular weight and polymeric materials can be (and many have already been) used as conducting systems. The chemical flexibility of many molecular systems also allows for using them as information-processing materials, whose action is based on their photochromic properties. A relation between properties of individual molecules and those of macroscopic molecular systems allows one to envisage construction of molecular-scale devices. However, due to limitations associated with technological problems (construction of molecular-scale elements, their addressing, quantum-mechanical (size) limitations, etc.), the construction of such elements is still a problem that awaits solution.