Crystallography beyond the Bragg Peaks

Diffuse scattering contains information on the real structure of disordered crystals that cannot be deduced from conventional structure analysis based on Bragg reflections. In this article the historical development, current state-of-the-art and future perspectives of diffuse scattering are described. The focus is on the last twenty years, in which progress in X-ray instrumentation and computer-aided modeling has transformed diffuse scattering research from a qualitative to a quantitative discipline. Examples of cutting edge diffuse scattering experiments and modern real structure modeling techniques are given.