Structures of the lovozerite type - a quantitative investigation

The structure of lovozerite is derived from perovskite. For 24 members of the lovozerite family an aristotype is postulated. The method of quantitative comparison using the concept of mappings is applied to the lovozerite family using the aristotype as a 'structural unit'. The method is extended to relationships of symmetry-type II, i.e. the derived structure and the aristotype have only a common subgroup, the remaining non-common symmetry of the derived structure is used as 'distribution' symmetry for the structural unit. The numerical results are discussed in detail. (orig.)