Lattice Constants of Tetragonal Perovskite Structured Solids

In this paper, a simple lattice constants (a and b) prediction model based on ionic charge theory of solid is proposed. The lattice constants of tetragonal perovskites exhibits a linear relationship when plotted on a log-log scale ionic radii r(av) (angstrom), but fall on different straight lines according to the ionic charge product of the compounds. This enables us to achieve improves predication performance of the lattice constant of structurally known perovskites. We have applied the proposed relation to ABX3 (A: large cation with different valance, B: transition metal, X: anion) and found a better agreement with the experimental data as compared to the values evaluated by earlier researchers.