Synthesis and Crystal Structure of LiCe(PO3)4

Abstract

The solid-state reactions of Li2CO3, CeCl3·7H2O and H3PO4 lead to a new lithium cerium polyphosphate, LiCe(PO3)4. This polyphosphate crystallizes in the monoclinic system with a C2/c space group. It was analyzed at room temperature using X-ray diffractometer data. The unit-cell parameters are a = 16.520(7)Å, b = 7.088(4)Å, c = 9.831(4)Å, β = 126.290(2), Z = 4 and V = 927.8(8)Å3. The crystal structure was refined based on 2875 independent reflections with I > 2σ(I). Final values of the reliability factors were improven considerably: R = 0.011 and Rw = 0.013. This mixed-metal rare-earth polyphosphate consists of a three-dimensional framework in which zigzag [(PO3)n]n-chains with a periodicity of four PO4 tetrahedra are connected through Li+ and Ce3+ ions. In this structure both Ce and Li occupy special positions (Wyckoff position 4e, site symmetry 2). © 2011 The Japan Society for Analytical Chemistry.