Carl Wilhelm Wagner (25.05.1901 -10.12.1977) — German physicist and physical chemist, a member of the Göttingen Academy of Sciences. Born in Leipzig. He graduated from the University of Leipzig (1924). In 1924–27 he worked at the University of Munich, in 1927–28 at Berlin, in 1928–33 at Jena, in 1933–34 at Hamburg, in 1934–47 at the Technical University of Darmstadt (professor from 1940), and in 1947–58 at the Massachusetts Institute of Technology (USA). In 1958–66 director of the Max Planck Institute for Physical Chemistry in Göttingen.
His main work was in semiconductor physics, solid-state physics, metallurgy and physical chemistry. He studied defects of the crystal lattice in ionic crystals and semiconductors and the part they play in heterogeneous catalysis and in reactions in the solid state. In 1930 he found that there are two types of semiconductor—electron and hole. With W. Schottky he developed (1930) the theory of electrolytic transport. Along with W. Schottky he is the founder of semiconductor physics in Germany.
A foreign member of the US National Academy of Sciences (1967).