An analytical method for indexing powder diffraction patterns of higher-symmetry substances

With the observation of equal numbers (to within experimental error) in Q/4, Q/8 and/or Q/12, where Q is the square of the reciprocal interplanar distance from the reflection lines, and the knowledge of how these numbers are related to the square of the reciprocal-lattice parameter, a^*2, for cubic, tetragonal and hexagonal systems, lines can be rapidly indexed and the lattice parameters computed.