Gilbert N. Lewis

Gilbert Newton Lewis (October 23, 1875 - March 23, 1946) was a famous American physical chemist known for his 1902 Lewis dot structures, his 1916 paper "The Atom and the Molecule", which is the foundation of modern valence bond theory, developed in coordination with Irving Langmuir, and his 1923 textbook Thermodynamics and the Free Energy of Chemical Substances, written in coordination with Merle Randall, one of the founding books in chemical thermodynamics. In 1926, Lewis coined the term "photon" for the smallest unit of radiant energy.
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