Robert S. Mulliken

Robert Sanderson Mulliken (June 7, 1896 – October 31, 1986) was an American physicist and chemist, primarily responsible for the early development of molecular orbital theory, i.e. the elaboration of the molecular orbital method of computing the structure of molecules. Dr. Mulliken received the Nobel Prize for chemistry in 1966.

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 * ...the more accurate the calculations became, the more the concepts tended to vanish into thin air.
 * about using old-fashioned chemistry to describe molecular structure, in Molecular Scientists and Molecular Science: Some Reminiscences, J. Chem. Phys. 43, S2 (1965).