Determination of B-cation chemical short-range order in perovskites from the total pair-distribution function

Short-range B-cation order affects the functional properties of many complex perovskites. However, current ability to measure the characteristics of such chemical short-range order (SRO) in perovskite-structured ceramics is limited. In the present study, two distinct methods are compared for the determination of the B-cation SRO parameters from the total scattering pair-distribution function (PDF). Both methods rely on reverse Monte Carlo refinements of the structural models but differ in the procedures used to extract the SRO characteristics. The accuracy of these methods was tested using synthetic PDF data generated for models of prototype Ca(Zr,Ti)O₃ solid solutions. One of the approaches developed in the present study, which proved to yield the most accurate results, was used to analyze the SRO of Ti and Zr in powder samples of Ca(Zr,Ti)O₃.