On the existence of PbBi3PO8: Its synthesis and crystal structure

The title compound crystallizes in the tetragonal system, a = 11.733(2) Å, c = 15.587(3) Å, I4 mm, Z = 10. Data were collected at the Argonne National Laboratory synchrotron source at λ = 0.15359 Å. Least squares refinement on F2 converged to R1 = 0.039. The oxygen coordination polyhedra around Bi and Pb display the distortions typical of 6s2 lone-pair atoms. One Bi is disordered. BiO bonds vary from 2.08(2) to 2.96(1) Å. One Pb is in cubic coordination to oxygen and the second Pb is bonded to six oxygen atoms that form a rectangular pyramid and a seventh oxygen is off one of the rectangular faces of the pyramid. PbO bonds vary from 2.303(6) to 2.804(17) Å. Of the two crystallographically independent P one is in a single tetrahedral coordination while the second is at the center of two disordered tetrahedra. Units of OM4 tetrahedra, M = Bi/Pb, articulate into a three-dimensional framework by corner and edge sharing that is strengthened by corner sharing with PO4 moieties.