Cell, symmetry and basic structure of a new ferrimagnet, Ba5Zn2Ti3Fe12O31

Abstract A new ferrimagnetic species, 18H, has been characterized: hexagonal, a = 5.844 A , c = 43.020 A , P 6 3 / mmc, Z = 2, Ba 5 Zn 2 Ti 3 Fe 12 O 31 , D x = 5.55 g/cm 3 , D m = 5.56 g/cm 3 . The nine-anion-layer primitive repeat group along c features five contiguous Ba-containing layers. Basically the structure consists of a six-anion-layer Y block alternating with a three-anion-layer barium titanate block. Such features are new to the extensive hexagonal ferrite group of ferrimagnetic materials.