Actinides: the unusual world of the 5f electrons

The original Periodic Table provided for only 92 elements but developments in atomic physics have greatly extended it. Fourteen elements, the actinides, now follow actinium, number 89 in the Table. Their electronic configurations are of much theoretical interest and their preparation demands - in addition to containing their high radioactivity - the development of novel chemical techniques. This article reviews the physics and chemistry of the actinides and suggests some possible applications. (author)