The electric conductivity at elevated temperatures was measured for the series of orthophosphates LaxYb1/3 − xZr2(PO4)3, where x = 0, 1/18, 1/9, 1/6, 2/9, 5/18, and 1/3. They belong to the family of NASICON compounds, which were known to possess trivalent ionic conductivity. The method of infrared spectroscopy was applied to determine structural transition P3̄ → P3̄c. These data correlated well with the observed conductivity values plotted against composition.

Multivalent Ionic Conductivity in the Series of Phosphates LaxYb1/3-xZr2(PO4)3 with NASICON Structure. D.M.Bykov, G.S.Shekhtman, A.I.Orlova, V.S.Kurazhkovskaya, E.Y.Borovikova, V.Y.Volgutov: Solid State Ionics, 2011, 182[1], 47-52