FRANCK, JAMES

FRANCK, JAMES (1882–1964), physicist and Nobel prize winner. Franck, who was born in Hamburg, studied chemistry at Heidelberg and Berlin. He then devoted himself mainly to physics. In 1920 he became a professor of experimental physics, directing the second Physical Institute at Goettingen. In 1925 he and gustav hertz jointly received a Nobel prize for their discovery of the laws governing the impact of an electron on an atom, corroborating Bohr's "obstacle" theory of spectra, according to which atoms cannot absorb any energy below a certain level. In 1933, after the Nazi regime was established, Franck moved to the United States. He became a faculty member of Johns Hopkins University and the University of Chicago and made further investigations into the structure of matter, especially the kinetics of electrons. He also developed brilliant optical methods for determining the dissociation temperatures of chemical combinations from molecular spectra, and confirmed the assumptions on which modern atomic theory rests. In addition, he carried out important investigations in photochemistry. -BIBLIOGRAPHY: Mc-Callum and Taylor, Nobel Prize Winners (Zurich, 1938); American Men of Science (1965). (J. Edwin Holmstrom)