Magnetic relaxation properties and clustering of iron ions in polymers and glasses

Information on the relaxation Moessbauer experiments on polymers and glasses is summarized. Special attention is devoted to the heterogeneous distribution of iron atoms in host matrices. Three types of iron clusters are discussed: clusters containing a few but definite number of metal ions, clusters consisting of small grains in a host matrix, and regions in non-crystalline material which contain an enriched zone of metal ions. They have been studied by Moessbauer spectroscopy. (author)