Pb2BiO2PO4, a new oxyphosphate

摘要: Abstract Pb 2 BiO PO 4 is orthorhombic with space group Pnma , a =5.930(4), b =9.079(10), c =11.473 (6) A at room temperature, Z =4, and congruent melting point of 860°C. The structure was solved from single crystal powder diffraction data. ion can occupy two energetically equivalent positions causing oxygen atoms to be disordered. described on the basis several motifs. Infinite chains rectangular pyramids formed by edge-sharing parallel axis that are linked lead phosphate anions. Bi also considered as present in trigonal prismatic environment which one corner triangular face unoccupied. Presumably 6s lone pair extends toward apex. bonded six forming distorted octahedron when distances less than 3 considered. When additional ions 3.20(9) 3.24(5) part coordination polyhedron it bisdisphenoid. This related structures found many M II X O 6 phases. Raman spectrum shows expected frequencies for . In addition observed assigned P–O–Bi P–O–Pb linkages. Intense bands 143 150 cm −1 attributed internal vibrational modes pyramid.