Langmuir, Irving (lăngˈmyōr) [key], 1881–1957, American chemist, b. Brooklyn, N.Y. Associated (1909–50) with the research laboratory of the General Electric Company, he introduced atomic-hydrogen welding, invented a gas-filled tungsten lamp, and by his work on the high vacuum contributed greatly to the development of the radio vacuum tube. He extended the work of Gilbert Lewis on electron bonding, evolving the Lewis-Langmuir theory of atomic structure. In his research on surface tension and surface chemistry he developed a new technique (employing monolayers, i.e., layers of molecules one molecule thick) for the study of molecules, which has applications in research on microorganisms and toxins and in other studies contributing to advances in immunology. For his contributions in surface chemistry he received the 1932 Nobel Prize in Chemistry. It was Langmuir who discovered that the introduction of particles of dry ice and iodide into a cloud of low temperature containing sufficient moisture in tiny droplets triggered a chain reaction producing rain or snow, depending on the condition of the weather.
See his works, ed. by C. G. Suits and H. E. Way (12 vol., 1960–62); study by A. Rosenfeld (1966).