Accurate lattice constants from multiple reflection measurements. II. Lattice constants of germanium silicon, and diamond

The lattice constants of a diamond platelet and of large single, undoped, crystals of silicon and germanium have been determined from measurements of multiple diffraction patterns by the method described in Part I [Post (1975). J. Appl. Cryst. 8, 452–456]. The mean values, based on measurements of eight to twelve reflections, and their standard deviations are: diamond a = 3.566986 Å, Aa/a = 2.6 × 10−6; silicon a = 5.430941 Å, Aa/a = 2 × 10−6; germanium a = 5.657820 Å, Δa/a = 1.6 × 10−6.