The formation of the 230 crystallographic space groups, as the result of the combination of 14 Bravais lattices with 32 point groups when translational symmetry elements are included, will be discussed.

Scattering of X-rays on a crystal lattice and its mathematical description (Fourier transformation, scattering factor calculations, and reciprocal lattice) will be discussed.

General instrumentation will be described: anatomy of a modern diffractometer, radiation sources, beam optics and detectors.

Procedures are often used to prepare single crystals suitable for structure determination by X-ray crystallography will be discussed.

Recording the diffraction pattern (i.e. measuring the intensity and angle of diffracted X-rays), indexing, integration and scaling of data will discussed. Resolution limits, target values of completeness and redundancy will be critically assessed.

Structure solution is the process of obtaining accurate phases in order to build a molecular model. General structure solution methods (direct methods, Patterson function) will be discussed.

Aspects of importance to structure refinement, in particular thermal motion, convergence, R-factors and goodness of fit.

During this lecture, students will be familiarized with the properties and origin of proteins. They will learn how proteins are isolated from original sources or heterologously produced in various production systems. They will then learn the principles that are applied in isolating and purifying proteins. A third aspect will be to learn how proteins may be induced to form regular, three-dimensional arrays or crystals.

Crystallographic databases as the repositories of huge amounts of useful crystallographic data will be discussed, with particular focus on the Cambridge Structural Database for small molecules.

During this practical session, students will set up crystallization plates with lysozyme by sitting and hanging drop.

Introduction to XPREP and OLEX2.

During this lecture, students will learn about the critical factors in obtaining complete diffraction data from macromolecular crystals to as high a resolution as possible. The principles behind evaluating diffraction images and converting the data to tables of reflections will be explained. In addition, the nature of these reflections will be discussed.

Practical examples of solving and refining routine structures will be covered with hands-on experience.

Practical examples of solving and refining routine structures will be covered with hands-on experience.

During this lecture, students will be taught the principles of solving protein structures from diffraction data will be illustrated. The limitations of diffraction experiments will be outlined and how these can be overcome.

This will be a practical session at the University of Cape Town, where diffraction data will be collected – ideally from crystals grown by students of the course.

Powder X-ray diffraction is an important technique in the characterization, identification and quantification of materials in the solid state. The course will include the following topics: an introduction to PXRD diffraction physics, instrumentation (different geometries), the interpretation of profiles (basic phase identification), common pitfalls (preferred orientation, sample size, etc.), particle size analysis and if time permits, an introduction to Rietveld (and /or Pawley) refinement.

Diffraction data sets collected on the diffractometer during the previous session will be used to solve the structure either by using anomalous data or by molecular replacement.

These two session will build on the topics introduced in the previous session (MS5); they will extend Rietveld method to structure solution and refinement. If time permits, it will expand on Pawley and le Bail whole pattern methods for phase purity analysis. In the hands-on tutorial session attendees will be introduced to the use of single-crystal X-ray diffraction data and the CSD (calculation of PXRD traces, preferred orientation tool, etc.) in the interpretation of PXRD profiles.