- Person
- James Franck
- Lived
- 1882–1964
- Field
- Atomic physics
- From
- German-American
The story
After leaving Germany in 1933, James Franck spent a year at Niels Bohr’s institute in Copenhagen. He planned to continue his research on the fluorescence of vapours and liquids, but under Bohr’s influence he and his assistant Hilde Levi began to study the biological side of these reactions, publishing two papers on the fluorescence of chlorophyll. That work drew him to one of the most important processes on Earth: photosynthesis, the way plants use light to make sugars from carbon dioxide and water.
The problem was far more complicated than the collisions between electrons and atoms that had won him a Nobel Prize, but it drew on the same theme that ran through all his work, the exchange of energy between light, atoms and molecules. Lise Meitner later said she saw no break between his early and later research, which always came back to that question.
In 1935 Franck moved to Johns Hopkins University in Baltimore, where the Rockefeller Foundation gave him $10,000 for equipment but the university could not pay for skilled staff. In 1938 he became professor of physical chemistry at the University of Chicago, where his work on photosynthesis had attracted interest. There he wrote a paper on photochemical processes in crystals with Edward Teller and worked with the plant physiologist Hans Gaffron.
After wartime service directing the chemistry division of the Manhattan Project’s Metallurgical Laboratory, Franck became professor emeritus in 1947, at 65, but kept working and led Chicago’s Photosynthesis Research Group until 1956. In 1955 the American Academy of Arts and Sciences awarded him its Rumford Medal for his work on photosynthesis. The Royal Society, electing him a Foreign Member in 1964, cited his contributions to problems of photosynthesis alongside his physics.
Franck died in 1964, and three years later the University of Chicago named the James Franck Institute in his honour. His career showed how the precise tools of physics could be turned to the chemistry of living things.
Why it matters
Franck helped bring the tools of physics to the study of photosynthesis, the process on which nearly all life and food on Earth depends.
About James Franck
Nobel physicist whose electron-collision experiment proved atoms have quantised energy levels; he resigned in protest in 1933 and later led the Franck Report against a surprise atomic attack.
More about James Franck
- James Franck championed women in physicsJames Franck actively advanced the careers of women physicists, notably Hertha Sponer and Hilde Levi, at a time when few women held research posts.
- The Franck–Condon principle explains how molecules glowIn 1925 James Franck proposed the mechanism, later developed by Edward Condon into the Franck–Condon principle, that governs how molecules absorb and emit light.
- James Franck made Göttingen a world centre of physicsFrom 1920 to 1933 James Franck and Max Born made Göttingen a world centre of quantum physics, training scientists such as Blackett, Condon and Oppenheimer.
- James Franck proved atoms take energy in fixed stepsIn 1914 James Franck and Gustav Hertz showed electrons lose exactly 4.9 electronvolts to mercury atoms, proving atomic energy is quantised; they won the 1925 Nobel Prize.
- James Franck resigned in protest against Nazi lawsOn 17 April 1933 James Franck, exempt as a war veteran, resigned his Göttingen chair in protest, the first German academic to do so over the Nazi civil service law.
- The Franck Report urged a warning before the bombOn 11 June 1945 the Franck Report urged that the atomic bomb be demonstrated in an uninhabited place rather than used on Japanese cities without warning.
- Franck helped dismissed Jewish scientists find workBefore leaving Germany in November 1933, James Franck helped Frederick Lindemann of Oxford find posts abroad for Jewish scientists dismissed by the Nazis.
Sources
- James Franck – Biographical NobelPrize.org
- James Franck Atomic Heritage Foundation
- James Franck Jewish Virtual Library
Another act of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.