Approaches to modelling the behaviour of ceramics and minerals

In order to understand the behaviour of ceramics and minerals at an atomic level a wide variety of modelling techniques are presently used, and one of the purposes of this workshop is to bring these together. At the most expensive end of the spectrum are the nb initio electronic structure calculations, which can accurately model the anergies of bonds of varying strength. Al the other end are simple, almost naive, models where interaction energies are approximated to be of either infinite or zero strength. In between there is a variety of empirical schemes of varying degrees of complexity. Which approach is most appropriate depends on what is wanted from a model, that is, what are the questions that are being asked. In this introductory review I comment on the virtues of different approaches, and highlight the comparisons with reference to a number of studies where combinations of different approaches have been used to good effect.