Acta Crystallographica Section E (Apr 2011)
Li2Ca1.5Nb3O10 from X-ray powder data
Abstract
Lithium calcium niobium oxide (2/1.5/3/10), Li2Ca1.5Nb3O10, has been synthesized by conventional solid-state reaction. Its structure consists of triple-layer perovskite slabs of corner-sharing NbO6 octahedra interleaved with lithium ions; Ca cations partially occupy the perovskite A sites at 75% occupancy probability. All eight atoms in the asymmetric unit are on special positions: one Nb atom has site symmetry 4/mmm; the second Nb, both K, the Sr and two O atoms have site symmetry 4mm; the remaining two O atoms have site symmetries 2mm. and mmm., respectively.