Leo Yaffe (July 6, 1916 - May 14, 1997) was a Canadian nuclear chemistry scientist and a proponent of the peaceful uses of atomic energy.

Born in Devils Lake, North Dakota, his family moved to Winnipeg in 1920. He studied at the University of Manitoba receiving a B.Sc.(Hons) in 1940, a M.Sc. in 1941, and was awarded an honourary D.Sc. in 1982. He received a PH.d. in 1943 from McGill University.

In 1943, he was recruited by Atomic Energy of Canada Ltd (AECL) to work at the Université de Montréal, moving to the Chalk River Lab, on the banks of the Ottawa River, in Ontario, at the end of the war. He remained with the AECL until 1952.

In 1952, he moved to Montreal where the J.S. Foster cyclotron had just been built at McGill University. In 1958 he became the Macdonald Professor of Chemistry.

From 1963 to 1965 he was director of research at the International Atomic Energy Agency in Vienna. Returning back to McGill he was appointed head of the Department of Chemistry until 1972. In 1974 he was appointed Vice-Principal (administration) which he held until he retired in 1981. From 1981 to 1982, he was the president of the Chemical Institute of Canada.

He married Betty Workman and has two children: Carla Krasnick, and Mark Yaffe.

Honours

• Fellow, Royal Society of Canada, 1959
• Doctor of Letters, Trent University, 1980
• Officer, Order of Canada, 1988
• Prix du Québec, 1990

Quotes

• "People, unfortunately, tend to equate nuclear with bombs. I'm a passionate believer in the peaceful purposes of nuclear energy. What people don't realize is how many people are being helped to surmount medical problems with nuclear medicine."
• "The transmission of knowledge from one generation to the next remains for me the most noble of the professions."