Magnetic properties of alkali metal clusters in zeolite cages

Magnetic properties are reviewed for alkali metal clusters incorporated in zeolite cages. The average number of ns-electrons in a cluster can be changed by control of the loading density of the guest alkali metal. The magnetic properties strongly depend on the number of ns-electrons and the deformation of clusters. The intercluster interaction as well as the local electronic state play an important role in the macroscopic magnetic properties, such as ferromagnetism.