Amyand David Buckingham. 28 January 1930—4 February 2021

David Buckingham was a chemical physicist and theoretical chemist who made fundamental contributions to the understanding of optical, electric and magnetic properties of molecules. Born in Australia, he was an undergraduate at the University of Sydney and the first PhD research student of John Pople (FRS 1961) at Cambridge, and there he made significant advances in the theory of intermolecular forces and nonlinear optics. He then moved to Oxford, where he and his group performed the first direct measurement of a molecular electric quadrupole moment. He was elected to the first chair of theoretical chemistry at the University of Bristol, where he wrote a particularly influential article on molecular moments, higher-order polarizabilities and intermolecular forces. His next appointment was at the University of Cambridge as the first holder of the 1968 Chair of Chemistry, and he was head of a distinguished department of theoretical chemistry for 28 years. With colleagues he pioneered experiment and theory on vibrational optical activity and developed a powerful model to predict the structures of weakly-bound molecules. A man of broad interests and achievements, he played first class cricket in the 1950s.