Application of a new virtual crystal approach for the study of disordered perovskites Original Research Article

The “virtual crystal” (VC) approach is a tractable way of studying configurationally disordered systems; the potentials which represent atoms of two or more elements are averaged into a composite atomic potential. This approach has the advantage that a single configuration with a smaller unit cell represents the disordered system. However, due to the different local environment of the virtual atom, some properties may not be reproduced. In this work, we develop a new virtual crystal approach and apply it to the study of the stress-induced phase transition in Pb(Zr1/2Ti1/2)O3. We compare four averaging algorithms for the construction of the virtual atom pseudo-potentials and we assess the accuracy of each by comparing with a superlattice prediction of the equations of state.