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Edwin M. McMillan *33
Chemistry 1951


The Nobel Prize in Chemistry in 1951

The Nobel Prize in Chemistry 1951 was awarded jointly to Edwin Mattison McMillan and Glenn Theodore Seaborg "for their discoveries in the chemistry of the transuranium elements."


The heaviest element existing in nature is uranium, which has an atomic number of 92. All the heavier elements are radioactive and quickly decay. It became apparent, however, that they can be created by bombarding atoms with particles and atomic nuclei. In 1940 Edwin McMillan used a particle accelerator to radiate uranium with neutrons and proved that an element with an atomic number of 93 had been created. It was named Neptunium. Edwin McMillan also contributed to the mapping of additional heavy elements and isotopes.

[Curator’s note: The following material quotes and paraphrases extensively from articles posted by the Nobel Prize Committee and the Princeton Alumni Weekly; see Sources below for details.]

Early life

Edwin Mattison McMillan was born on September 18, 1907, at Redondo Beach, California. He is the son of Dr. Edwin Harbaugh McMillan, a physician, and his wife, Anne Marie McMillan, née Mattison, who both came from the State of Maryland and were both of English and Scottish descent. He spent his early years in Pasadena, California, and obtained his education in that state.

Princeton University for his graduate degree

McMillan attended the California Institute of Technology, obtaining a B.Sc. degree in 1928, and taking his M.Sc. degree a year later, then transferring to Princeton University for Ph.D. in 1932.

McMillan’s Ph.D. thesis, under Professor E. U. Condon, examined the generation of a molecular beam of hydrogen chloride nuclei in a nonhomogeneous electric field. In parallel, McMillan received a thorough education in experimental nuclear physics at Princeton. He published a paper on the isotopic composition of lithium in the sun from spectroscopic observations immediately after receiving his Ph.D. He then won a highly prized National Research Council (NRC) fellowship, supporting him at any university of his choice.

University of California Berkeley

The same year he entered the University of California at Berkeley as a National Research Fellow. The thesis he submitted for Ph.D. was in the field of molecular beams, and the problem he undertook as a National Research Fellow was the measurement of the magnetic moment of the proton by a molecular beam method.

After two years on this work and one as a research associate he became a Staff Member of the Radiation Laboratory under Professor E.O. Lawrence, studying nuclear reactions and their products, and helping in the design and construction of cyclotrons and other equipment, and a member of the Faculty in the Department of Physics at Berkely, being appointed Instructor in 1935, Assistant Professor in 1936, Associate Professor, 1941, and Professor in 1946.

National defense research

During the Second World War, McMillan was on leave from November, 1940, to September, 1945, engaged on national defense research, serving (1940-1941) in the Radiation Laboratory, Massachusetts Institute of Technology; (1941-1942) U. S. Navy Radio and Sound Laboratory, San Diego; (1942-1945) Manhattan District, Los Alamos.

In 1942 he left Berkeley to work with J. Robert Oppenheimer on the Manhattan Project. He often questioned the ability of mankind to control the use of the atom bomb. After WWII he returned to Berkeley and continued extensive research efforts.

It was during 1945 that he had the idea of “phase stability” which led to the development of the synchroton and synchro-cyclotron; these machines have already extended the energies of artificially accelerated particles into the region of hundreds of MeV and have made possible for important research .

In 1950, he received the Research Corporation Scientific Award and in 1951 the Nobel Prize. McMillan returns to the University of California Radiation Laboratory

McMillan returned to the University of California Radiation Laboratory as Associate Director from 1954-1958, when he was raised to Deputy Director and finally Director, in the same year.

Professor McMillan was a Fellow of the American Physical Society and the American Academy of Arts and Sciences, a member of the National Academy of Sciences and the American Philosophical Society, and from 1954-1958 he served on the General Advisory Committee to the Atomic Energy Commission. In 1960 he was appointed to the Commission on High Energy Physics of the International Union of Pure and Applied Physics. In 1963 he shared the Atoms for Peace Award with Professor V. I. Veksler. An honorary doctorate in science was awarded to him by the Rensselaer Polytechnic Institute in 1961, and by Gustavus Adolphus College in 1963.

Edwin M. McMillan died on September 7, 1991.


From Nobel Lectures, Chemistry 1942-1962, Elsevier Publishing Company, Amsterdam, 1964.The Nobel Foundation 1951. Edwin M. McMillan – Biographical.

Edwin M. McMillan – Facts.

The Nobel Prize in Chemistry 1951.

National Academy of Sciences: Edwin Mattison McMillan 1907-1991 by J. David Jackson and W.K.H. Panofsky, p. 217


Edwin McMillan in Wikipedia

Atomic Heritage Foundation: Edwin McMillan

PAW: The List

PAW Memorial: Edwin N, McMillan