The crystal structure of the phosphate eulytite Ba3Bi(PO4)3

Ba3Bi(PO4)(3) crystallizes with the eulytite structure and the cubic space group I (4) over bar 3d. X-ray crystallography has allowed us to determine the following crystal data: a = 10.5036(4) Angstrom, V = 1158.8 Angstrom(3), Z = 4, D-cal = 5.19 g/cm(3), D-exp = 5.02 g/cm(3), The structure was solved on a single crystal, using 343 independent reflections, with R1 = 0.0379 (wR2 = 0.0752). It could be viewed as built up from independent [PO4](3-) tetrahedra, lying along rods parallel to the axis and to [001]. The rods are arranged in a manner to delimit pairs of irregular pentagonal tunnels. In addition to two oxygen sites identified in the title structure, as previously reported for other compounds, two different sites were refined for barium and bismuth contrary to what has been reported in equivalent eulytite compounds. (C) 2000 Elsevier Science Ltd. All rights reserved.