born Oct. 9, 1879, Pfaffendorf, near Koblenz, Ger.
died April 23, 1960, Berlin, W.Ger.
German physicist.
He taught at the University of Berlin (1919–43). He was the first to use a crystal to diffract X ray s, demonstrating that X rays are electromagnetic radiation similar to light and that the molecular structure of crystals is a regularly repeating arrangement. For his work in crystallography he received a 1914 Nobel Prize. He championed Compton effect , and the disintegration of atoms.