MARCUS, RUDOLPH ARTHUR

MARCUS, RUDOLPH ARTHUR (1923– ), chemist and Nobel Prize winner. Marcus was born in Montreal, Canada, and educated there at McGill University. He taught at the Polytechnical Institute of Brooklyn, n.y., 1951–64, at the University of Illinois, 1964–1978, and at the California Institute of Technology, where he became the Arthur Amos Noyes Professor of Chemistry in 1978.

Marcus was awarded the Nobel Prize in chemistry in 1992 for his mathematical analysis of the cause and effect of electrons jumping from one molecule to another, ideas which he developed from 1956 to 1965. When electrons in molecules in a solution jump from one molecule to another, the structure of both molecules changes. The occurrence of this change temporarily increases the energy of the molecular system, resulting in a "driving force" for electron transfer. It was only in the 1980s that Marcus' theories were finally confirmed by experiments. His work has been useful in understanding many complicated chemical reactions, among them photosynthesis. Marcus is also well known for his theory of unimolecular reactions in chemistry, the rrkm theory, which more than 50 years after its development is still the standard theory in the field. It treats the fragmentation of high-energy molecules, as in the atmosphere and in combustion. His research also ranges from the strange fluorescent behavior of nanoparticles to the anomalous isotopic composition of the ozone in the stratosphere and of the earliest solids in the solar system.