The experimental determination of the soundness of crystals from X-ray and density measurements

A method is described which makes possible the detection of imperfections in crystals of elements, compounds and solid solutions by the determination of molecular weights from X-ray and density measurements. Precision determinations of density and lattice constants are necessary for the calculations. It is shown that the elements Ag, Cu, Fe, Pb, Te and the compounds LiF, Pb(NO3)2 and calcite may be considered as having a normal structure, as the number of imperfect sites found does not exceed the possible error of determination of these imperfections. A normal structure is also shown by the tetragonal mixed crystals of the general formula (Zn, Cd, Co) [Hg(CNS)4] and by the α phase in solid solutions of the Ag–Zn system.