Physics in Perspective

, Volume 16, Issue 3, pp 293–343 | Cite as

The Franck-Hertz Experiments, 1911–1914 Experimentalists in Search of a Theory

With an appendix, “On the History of our Experiments on the Energy Exchange between Slow Electrons and Atoms” by Gustav Hertz


In 1911, James Franck and Gustav Hertz began a collaboration to investigate the nature of collisions of slow electrons with gas molecules that led to a series of carefully planned and executed experiments, culminating in their discovery of inelastic collisions of electrons with mercury vapor atoms in 1914. This paper tells the story of their collaboration and the eventual reinterpretation of their results as a confirmation of Niels Bohr’s new atomic theory, largely as a result of experiments done in North America during the Great War.


James Franck Gustav Hertz John Sealy Edward Townsend J. J. Thomson Niels Bohr Robert Pohl Wilhelm Westphal Lise Meitner Ernest Rutherford electron ion mobility ionization affinity resonance 


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© Springer Basel 2014

Authors and Affiliations

  1. 1.Saint CloudUSA

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