The Reciprocal Lattice

Abstract

So far, it has been shown how the knowledge of the unit cell of a crystal makes it possible to construct all possible sets of lattice planes (hkl) and to calculate their spacings d and the scattering angle of the corresponding reflections hkl. In order to measure the many reflections required for a structure determination, it is necessary to determine the precise orientations of the crystal relative to the X-ray beam required to bring each set of lattice planes in turn into the position that fulfils the Bragg condition and causes the scattered radiation to fall on the detector system.