KATHLEEN Y. LONSDALE (1903 - 1971). The Structure of the Benzene Ring. (Nature 1928, 122, 810.)
Lonsdale studied mathematics and physics and received a B.Sc. degree at the age of nineteen from Bedford College for Women with highest honors. She took first place in the University of London list and one of her examiners, William H. Bragg, was so impressed that he offered her a post in his research team to work on the crystal structure of organic compounds by X-ray analysis. Thus her scientific career began in 1922, first at University College and then at the Royal Institution in London, where she remained for most of the rest of her professional career. In 1945 she became the first woman to be admitted as a Fellow of the Royal Society of London. She was appointed Dame Commander of the British Empire in 1956, received the Davy Medal of the Royal Society in 1957 and was its vice-president from 1960-1961. In 1966 she was president of the International Union of Crystallography and president of the British Association from 1967 to 1968.
When Lonsdale began her work on organic compounds, the structure of many simple and some quite complex inorganic substances had been deduced. But little was known about the dimensions and exact dimensions of organic molecules until Lonsdale's breakthrough in 1928. Not only was the result new, but the method by which she solved the structure of hexamethylbenzene was significant: in a real sense, it was the first structure solved by direct methods, a technique that was brought to fuller development by Herbert Hartmann and Jerome Karle in the 1950s. Lonsdale's work on hexamethylbenzene not only proved that the benzene ring was hexagonal and planar, but also gave its precise dimensions for the first time.
Lonsdale made many other research contributions over her career: she carried out important work on the magnetic anisotropy of crystals, the precision of X-ray diffraction experiments, the elastic properties of crystals, and the structure of diamond allotropes.
Kathleen Lonsdale had a profound influence on the development of X-ray crystallography and related fields in chemistry and physics. Very few have made so many important advances in so many different directions.
Complete Dictionary of Scientific Biography. Detroit: Charles Scribner's Sons, 2008, v8, p484-486.