Sir William Lawrence Bragg with a model of a protein molecule while visiting Adelaide, 24 October 1960.

William Lawrence Bragg (known as Lawrence) was born in Adelaide on 31 March 1890. At the age of 15, Lawrence completed his secondary education at St Peter's College. He enrolled at the University of Adelaide, studying mathematics, chemistry and physics. Like his father, physicist William Henry Bragg, Lawrence then continued his studies at Cambridge University.

In 1912, the German physicist Max von Laue proved that x-rays were waves of light with a very short wavelength by diffracting them through crystals. Lawrence, who had just completed his degree, took up von Laue's work and began his own experimentation with x-rays and crystals, eventually developing Bragg's Law - a formula which expresses the relationship between the wavelength of the x-ray, the angle at which the x-ray enters the crystal and the distance between the layers of the crystal. The law can be used to determine the arrangement of atoms inside crystals. Meanwhile, William had perfected a piece of equipment called an x-ray spectrometer with which father and son could conduct their x-ray crystallography experiments. For their collaborative work, Lawrence and William were awarded the 1915 Nobel Prize for Physics. Lawrence was 25, the youngest ever recipient of the award.

Lawrence served in France during the First World War, experimenting with using sound-ranging to identify the location of enemy guns. He received an OBE and the Military Cross in 1918. After the war, he took up a post as Professor of Physics at Manchester University. Other positions held during his career include Director of the National Physical Laboratory and Cavendish Professor of Experimental Physics, Cambridge.

Lawrence married in 1921 and he and his wife Alice had two sons and two daughters. He was knighted in 1941. Lawrence Bragg died on 1 July 1971.

Bragg, Lawrence, Sir, 1890-1971

Jenkin, John. The Bragg family in Adelaide: a pictorial celebration, [Adelaide]: University of Adelaide Foundation in conjunction with La Trobe University, c1986

Jenkin, John G. William and Lawrence Bragg, father and son : the most extraordinary collaboration in science, Oxford ; New York : Oxford University Press, 2008

Thomas, John M and Sir David Phillips, eds. Selections and reflections: the legacy of Sir Lawrence Bragg, Northwood, Middlesex : Science Reviews, c1990

Nobel e-museum: See Lawrence Bragg biography and William Bragg biography