9420699 Metzger The goal of this project is the synthesis of electron donor-acceptor molecules that can be used as fast unimolecular rectifiers of electrical current at the ultimate molecular, or nanometer, limit of electronic processes. The molecules will be tested as one molecule thick Langmuir-Blodgett films configured on metal substrates such that the molecular conductivity can be studied by scanning tunneling microscopy. In addition, photo-excitable molecules will be synthesized and tested as unimolecular photodiodes, and suitable doping schemes will be devised to explore the behavior of these devices as molecular transistors. %%% This interdisciplinary research project will cover aspects of chemical synthesis, physical characterization, and the design of fast unimolecular rectifiers, photodiodes, and transistors at the ultimate molecular or nanometer scale of electronic behavior. This proposed study is crucial to the development of next generation, molecular based electronic devices particularly in view of advances in this area in Europe.