Robert S. Mulliken
Born: 7 June 1896, Newburyport, MA, USA
Died: 31 October 1986, Arlington, VA, USA
Affiliation at the time of the award: University of Chicago, Chicago, IL, USA
Prize motivation: "for his fundamental work concerning chemical bonds and the electronic structure of molecules by the molecular orbital method."
Prize share: 1/1
The world around us consists of molecules that are composed of atoms. In Niels Bohr's atomic model, which is based on principles of quantum physics, electrons circle the atomic nucleus in different shells that contain a fixed number of electrons. The assumption was that attractive forces between the atoms in a molecule are the result of atoms sharing electrons to fill the electron shells. Beginning in the mid-1920s, Robert Mulliken applied quantum mechanics to the development of sophisticated models for the movement of electrons within a molecule, so-called molecular orbitals.