Crystal Structures of Silver Bismuthates Synthesized Under High Pressure

The silver bismuthate Ag2BiO3 is expected to contain bismuth in the nominal 4+ state, but Bi charge disproportionate in this insulator. A monoclinic distortion from Pnn2 to P2 at ~243 is observed. We explored the highly oxidized AgBiO3 in two phases: ilmenite and a newly synthesized phase at 6 GPa. The Bi-O interactions in all these silver bismuthates effect their properties, which we aim to probe with neutron diffraction. We therefore request 2 days on GEM in order to characterize all three materials. A standard ambient condition diffraction pattern will be sufficient for 1 g samples of AgBiO3 (ilmenite) and AgBiO3 (6 GPa) (~9 hours). As for Ag2BiO3, the diffraction pattern as a function of temperature for a 1 g sample will be measured over the range 10-300 K (~39 hours).