Structure types formed in the Ln-Al-{Si, Ge} systems.

This paper reviews the different structure types observed for alumosilicides and alumogermanides of rare earth metals. The analysis is based mainly on the coordination polyhedra around the atoms of the smallest size and on the stacking of segments cut from simple structure types. The 24 different structure types in which the 145 known rare-earth alumosilicides and alumogermanides can be crystallized are described in detail.