Abstract:
The aspects of structure, dipole ordering, and ionic conductivity of the Na3Cr2(PO4)3 crystal with the four polymorphic phases (α, α′, β, and γ) have been investigated. The features of the α-Na3Cr2(PO4)3 crystal structure and its dipole ordering and relaxation polarization in the low-temperature α, and α′ phases have been refined. The occurrence of Na3Cr2(PO4)3 dipole ordering in the α and α′ phases and high ionic conductivity in the β- and γ phases is attributed to the structural changes in the rhombohedral {[Me2(PO4)3]3−}3∞ crystal frame upon phase transformations α→α′, α′→β, and β→γ. A model for explaining the dipole ordering and ionic conductivity phenomena in Na3Cr2(PO4)3 is proposed.
Citation:
A. S. Nogai, S. Yu. Stefanovich, A. A. Bush, D. E. Uskenbayev, А. А. Nogai, “Dipole ordering and ionic conductivity in NASICON-Type Na3Cr2(PO4)3 structures”, Fizika Tverdogo Tela, 60:1 (2018), 25–32; Phys. Solid State, 61:12 (2019), 23–30