Conducting and dielectric properties of Na 3 Sc 2 (PO 4 ) 3

Abstract

in this article, the conductive and dielectric properties of polycrystal Na 3 Sc 2 (PO 4 ) 3 , which has three polymorphic α –, β –, γ – phases, are studied. The structural features of the α –Na 3 Sc 2 (PO 4 ) 3 crystal, as well as
dipole ordering and relaxation polarization in the α and β – phases, are refined. The occurrence of dipole ordering in
the α phase and partial disordering in β –Na 3 Sc 2 (PO 4 ) 3 , as well as high ionic conductivity in the β –, γ – phases
of the Na 3 Cr 2 (PO 4 ) 3 crystal is due to phase transformations α → β , β → γ , resulting in structural changes of the rhombohedral crystal framework {[M 2 (PO 4 ) 3 ] 3− } 3∞ . A model explaining the conductive and dielectric properties of Na 3 Sc 2 (PO 4 ) 3 is proposed.