Empirical model for the prediction of lattice constants in 1:2 ordered perovskites

Abstract Processing–structure relationships are at the heart of materials science, and predictive tools are essential for modern technological industries insofar as structure dictates intrinsic properties; however, few theoretical models exist for cation‐ordered perovskites. In this work, a combination of data mining and solid‐state synthesis was employed to collect structural data of 1:2 ordered (triple) perovskites. Three compositions within the (Ba 1 − x Sr x )(Mg 1/3 Ta 2/3 )O 3 system were synthesized using a conventional solid‐state mixed‐oxide method. X‐ray diffraction data showed evidence of long‐range 1:2 B‐site cation ordering for all compositions. Additional data for another 24 1:2 ordered compositions were mined from literature. Correlative models for the deviation in modified tolerance factor (Δ t′ ) were derived for each system, and a general model which is capable of predicting the pseudocubic lattice constants of such perovskites based solely on published ionic‐radii data developed.