We review in this paper the state of the art in Molecular Electronics, an emerging important branch of the nano-science. Molecular features, underlying potential possibilities of using molecules as electrical components, as well as molecular structures already in use in nano-devices, are discussed. Theoretical and experimental aspects of electron transport phenomena through such molecular structures are reviewed. We emphasize especially the competitive impact of tunneling effects, surface conductance and activation on the ensuing current-voltage characteristics. We discuss a number of new developments in this field, including possible applications of magnetic and optical phenomena in molecular systems. In conclusion we discuss future applications of molecular electronics.

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Numerical simulation of the conductance dependence on molecular configuration

About the Authors :
Prof. Mark A. Ratner
Mark Ratner was borne in Cleveland. He received his B.A. at Harvard in 1964, and the Ph.D. at the Northwestern University in 1969. He did postdoctoral work in Denmark and Munich. After teaching five years at the New York University he has joined in 1975 the Northwestern University. Here he has filled a number of duties, i.e. Head of the Chemistry Department, Vice-Dean of the Faculty of Sciences and Arts, and heading a group at the Center of Materials Research. Since 2000 he is the Morrison Professor of Chemistry. His research interests encompass a wide range of topics in chemistry and physics: nonlinear optical response properties of molecules; electron transfer and molecular electronics; dynamics of transport in polymer electrolytes; self-consistent field models for coupled vibration reaction dynamics; mean-field models for extended systems including proteins and molecular assemblies; photonics in nanoscale systems; energetics of DNA/protein binding and more. Prof. Ratner is the author of two books and about 400 scientific publications. He is a member of the National Academy of Science (USA) and the recipient of a number of awards, with the most significant being the Sloan Fellowship in 1972, the Feynman Award in nanotechnology in 2001 and a honorary doctorate from the Hebrew University.

Prof. Abraham Nitzan
Abraham Nitzan was born in Israel in 1944. He received his B.Sc. in chemistry in 1964, his M.Sc. in physical chemistry in 1966 (with Prof. Gidon Czapski), both from the Hebrew University, and his Ph.D. in 1972 (with Prof. Joshua Jortner) from Tel Aviv University. He had a postdoctoral Fulbright Fellowship at MIT, was a research associate at the University of Chicago, and taught at Northwestern University before joining the Faculty at Tel Aviv University. At TAU he has been a Professor of Chemistry since 1982 and also served as Chairman of the School of Chemistry in 1984-7the Dean of the Faculty of Science in 1995-8 and the Director of the Mortimer and Raymond Sackler Institute of Advanced Studies since 2004. Nitzan's research is in the field of chemical dynamics and transport phenomena in condensed phases. He was elected Fellow of the American Physical Society (1993) and the American Association for the Advancement of Science (2003) and has received the Kolthof Prize (1995), The Humboldt Award (1995) and the Israel Chemical Society Prize (2002).