Crystallographic structure solution

Abstract

The three-dimensional view of molecules at the atomic level provided by X-ray crystallography is not only extremely informative but is also easily and intuitively understood by humans, who very much rely on their vision. However, unlike microscopy, this technique does not directly yield an image. The structural model cannot be directly calculated from the diffraction data, as only the intensities of scattered beams and not their phases are experimentally accessible. In order to obtain the 3-dimensional structure phases have to be obtained by either additional experimental or computational methods. This is known as the phase problem in crystallography. In this manuscript we provide an overview of major milestones along the quest for the lost phases.