LEWIS, G.N.

born Oct. 23, 1875, Weymouth, Mass., U.S. died March 23, 1946, Berkeley, Calif. in full Gilbert Newton Lewis American chemist whose theory of the electron pair fostered understanding of the covalent bond and extended the concept of acids and bases. Lewis took his Ph.D. at Harvard University (1899), studied at the universities of Leipzig and Gttingen, and entered research in thermodynamics at the Massachusetts Institute of Technology, Cambridge (1905). He became professor of physical chemistry and dean of the College of Chemistry at the University of California, Berkeley in 1912. About 1916 Lewis began to advance the idea that a chemical bond could be formed by the sharing of valence electrons as well as by the transfer of electrons. He published his views in Valence and the Structure of Atoms and Molecules (1923). He also published, with Merle Randall, Thermodynamics and the Free Energy of Chemical Substances (1923), a textbook that became a classic work. The first to isolate deuterium, an isotope of hydrogen, he prepared a pure sample of heavy water (deuterium oxide) in 1933. His later researches contributed to the understanding of fluorescence, phosphorescence, and colour in organic substances.