Bonding mechanism of some simple ionic systems: Bader topological analysis of some alkali halides and hydrides revisited

The ability of Bader's charge density topology analysis to explain various material properties has been examined for simple ionic systems of alkali halides and alkali hydrides. It was established that despite the fact that most of them share the same rock salt crystal structure phase, some of them belong to different topological classes. This fact was used to explain various experimentally observed properties of these materials, and to discuss their deviations from expected trends. Some phase transitions observed in these systems, and their possible relation to changes in the charge density topology have been also investigated from the same point of view. Reasons for anion-anion bond formation in some of them and its features are discussed, as well.