James Franck (1882–1964) was a German physicist who is best known for his work in atomic and molecular physics. He was awarded the Nobel Prize in Physics in 1925, alongside Gustav Hertz, for their experiments demonstrating the behavior of electrons in atoms, which contributed significantly to the understanding of quantum mechanics. Franck's most notable contribution was the Franck-Hertz experiment, which provided evidence for the quantized nature of atomic energy levels.
