Fe-e' g Fe-a 1g 90.0 ○ 86.3 ○ In this paper, we further report the theoretical description of the structural and electronic properties of the high performance, rhombohedral Prussian white (R-PW) system. We observe a significant influence of ion concentration on the stability of Na preferred sites, which we attribute to the distortion and corresponding changes in lattice constants. By considering the geometry, we identify the interatomic distances in the face centered sites as an indicator of cation stability within the PB lattice. Furthermore, we demonstrate that the lattice distortion causes a migration away from the face cubic centered plane into the vertexes of the cubes during the phase transition. These results on R-PW shall be put into perspective by comparison with the cubic phase of Prussian white (C-PW), as well as with available experimental data. Additionally, we present first-principles electronic structure calculations to investigate the mobility of Na-ions in PB structures. Our focus is specifically on understanding the electronic properties that govern ion migration in these materials.