Synthesis and crystal structures of ‘Li 1.8K0.9M0.75Zr2.25O6.6’(M = Cu, Mg): a family of novel rocksalt–perovskite intergrowth phases
Abstract
The new phases, Li 1.8K 0.9M 0.75Zr2.25O6.6(M = Cu, Mg), have a novel rocksalt-perovskite intergrowth structure, with space group I4/mmm; a=; 4.1630(1), c= 18.1086(7)Å, Z = 2 for M = Cu and a= 4.1739(3), c= 17.971(2)Å for M = Mg, formed from ‘KZrO3’ perovskite units and rocksalt units ‘Li2M0.75Zr1.25O3.75’. A weak incommensurate supercell, not detected by X-ray diffraction, was characterised by electron diffraction; the supercell is parallel to [301] of the tetragonal subcell.