His wide-ranging research in physical science included chemical kinetics, x-ray diffraction, and adsorption of gases. He pioneered the theory of fibre diffraction analysis in 1921, and the dislocation theory of plastic deformation of ductile metals and other materials in 1934. He emigrated to Germany, in 1926 becoming a chemistry professor at the Kaiser Wilhelm Institute in Berlin, and then in 1933 to England, becoming first a chemistry professor, and then a social sciences professor at the University of Manchester.