Crystal structure modeling, electrical and thermal characterization of triple molybdates RbCrTi0.5(MoO4)3 (R=Fe, Cr)

The new triple molybdates of RbRTi0.5(MoO4)3 (R=Fe, Cr) were synthesized by a ceramic route at 580–600 °C. Their crystal structures have been refined by Rietveld analysis of powder X-ray diffraction data on the single crystal data of isostructural CsFeZr0.5(MoO4)3 (trigonal symmetry, space group R-3). The structure refinement converged to satisfactory values of the Rietveld parameters, Rp and Rwp, and goodness of fit. The lattice parameters, bond lengths and bond angles have been calculated from Full Proff program. The maximum value of RbCrTi0.5(MoO4)3 conductivity was 0.57×10–2 S cm–1 at 507 °C.

Crystal structure of RbRTi0.5(MoO4)3 (R=Fe, Cr) along c-axis.Figure optionsDownload as PowerPoint slideHighlights
► The new triple molybdates of RbRTi0.5(MoO4)3 (R=Fe, Cr) were synthesized.
► Their crystal structures have been refined by Rietveld analysis.
► This compounds have a superionic phase transition at temperature above ∼450 °C.
► RbCrTi0.5(MoO4)3 has rather high conductivity, approaching 0.57×10–2 S cm–1.