Frederick Charles Frank
Sir Frederick Charles Frank FRS (6 March 1911–5 April 1998), known as Sir Charles Frank, was a British theoretical physicist. He is best known for his work on crystal dislocations, including (with Thornton Read) the idea of the Frank-Read Source of dislocations. He also proposed the cyclol reaction in the mid-1930s, and made many other contributions to solid state physics, geophysics, and the theory of liquid crystals.
Early life and education 
He was born in Durban, South Africa, although his parents returned to England soon afterwards. He was educated at Thetford Grammar School and Ipswich School and went on to study chemistry at Lincoln College, Oxford, gaining a doctorate at the university's Engineering Laboratory.
During World War II he joined the Chemical Defence Experimental Station at Porton Down, Wiltshire but in 1940 was transferred to the Air Ministry's Assistant Directorate of Intelligence (Science) and spent the rest of the war with the Air Ministry.
After the war he moved to the University of Bristol Physics Department to do research in solid state physics, but switched to research on crystal dislocation. His work with Burton and Cabrera was to demonstrate the role dislocations played in the growth of crystals. Apart from crystal defects, his wide-ranging research interests at Bristol included the mechanical properties of polymers, the theory of liquid crystals and the mechanics of the interior of the Earth. He was appointed Reader in 1951, Melville Wills Professor in 1954 and Henry Overton Wills Professor and Director of the H.H. Wills Physics Laboratory in 1969. He retired in 1976 but remained active in attending conferences, writing papers and corresponding with colleagues well into the 1990s.
Honours and awards 
In 1994 he was awarded the Royal Society’s Copley Medal, its highest honour, "in recognition of his fundamental contribution to the theory of crystal morphology, in particular to the source of dislocations and their consequences in interfaces and crystal growth; to fundamental understanding of liquid crystals and the concept of disclination; and to the extension of crystallinity concepts to aperiodic crystals."
- Nabarro, F. R. N.; Nye, J. F. (2000). "Sir (Frederick) Charles Frank, O.B.E. 6 March 1911 -- 5 April 1998: Elected F.R.S. 1954". Biographical Memoirs of Fellows of the Royal Society 46: 177. doi:10.1098/rsbm.1999.0079.
- The Oxford Dictionary of National Biography. 2004. doi:10.1093/ref:odnb/68884.
- Frank, F. C. (1936). "Energy of Formation of 'Cyclol' Molecules". Nature 138 (3484): 242. doi:10.1038/138242a0.