PHYSICISTS A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z                    HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site Bragg, William Henry (1862-1942) British physicist who shared the Nobel Prize for Physics (1915) with his son, William Lawrence Bragg (1890-1971), for their analysis of X-ray spectra and the structure of crystals. He was knighted in 1920. A crystal is a substance consisting of a regular arrangement of atoms or molecules. In 1911 a German scientist, Max von Laue, discovered that when a narrow beam of X-rays falls on a crystal it is scattered as a regular pattern of diffracted beams. as the X-rays sweep through the crystal, the atoms scatter them, and these diffracted beams appear in directions where the scattered waves from all the atoms add their effects together. By studying this effect it is possible to find out how the atoms are arranged in the crystal. W. L. Bragg, then a student at Cambridge University, first used von Laue's complex method to work out the structure of common salt, sodium chloride (NaCl). W. H. Bragg then devised a far more powerful and simple instrument, the X-ray spectrometer, which made it possible to find more complex structures, such as that of diamond. The Braggs, father and son, were jointed awarded the Nobel Prize in 1915. Related category    • PHYSICISTS Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP