The changes in Madelung and non-electrostatic energies of Pb(Zr x Ti 1-x )O 3 (PZT) solid solutions in the high-symmetry ( Pm 3 m ) phase have been calculated using the heats of formation from the oxides. The non-electrostatic contribution (Δ E N ) decreases with decreasing x and becomes negative for compositions x ≤ 0.35, corresponding to perovskite tolerance factors t ≥ 1. Correlation of the strong increase in tetragonal distortion in the ferroelectric phase with more exothermic values of Δ E N suggests a softening of short-range repulsions for Ti-rich compositions. The influence of complex solid solution behaviour on the character of Pm 3 m ↔ P 4 mm transition is investigated by high-temperature specific heat and unit-cell parameter measurements. The implications of the thermochemical results with respect to mean-field theoretical descriptions of lattice instabilities and phase boundaries in the PZT system are briefly discussed.
No takes yet. Share an insight, caveat, or question.
Rossetti et al. (2002) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: