The indexing of single-crystal X-ray rotation photographs

A useful geometry is presented for analyzing X-ray diffraction patterns from a rotating crystal. From the basic diffraction condition, equations are derived for determining which reflections will appear in a given rotation range and where they will be found on the detector. Several procedures for indexing rotation photographs from protein crystals are discussed and the application of two of them to an X-ray diffraction study of hen egg-white lysozyme is described.