Crystal structures of a pentavalent bismuthate, SrBi₂O₆ and a lead bismuth oxide (Pb_1/3Bi_2/3)O_1.4

The crystal structures of a pentavalent bismuthate, SrBi2O6 with the PbSb2O6-type structure and a lead bismuth oxide, (Pb1/3Bi2/3)O1.4 with the fluorite-type structure were refined by using neutron diffraction data. The final R-factors were Rwp = 4.49, Rp = 3.46, RI = 4.50 and RF = 1.70% for SrBi2O6 and Rwp = 5.04, Rp = 3.93, RI = 5.47 and RF = 4.26% for (Pb1/3Bi2/3)O1.4. SrBi2O6 prepared from NaBiO3·1.4H2O is the first example of the bismuthate with the PbSb2O6-type structure. The fluorite-type lead bismuth oxide, (Pb1/3Bi2/3)O1.4 was obtained by heating the PbSb2O6-type lead bismuthate, PbBi2O5.9·H2O which was prepared also from NaBiO3·1.4H2O.