As with most perovskites, SrZrO$_{3}$ undergoes a number of phase transitions. The temperature-driven phase transitions are summarized by (Kumar, 2017).
We have arbitrarily labeled the phases from low- to high-temperature by Greek letters.
The former phase seems to be favored by experiment, but it does not share any subgroups with the $Pnma$ structure, so a direct phase transition is difficult. On the other hand the later structure does not show up in the experimental results in the ICSD, only in a theoretical calculation (ICSD 89356) by (Liu, 2012). (Kumar, 2017) mostly favor the first option, while (Fujimori, 2004) favor the second, albeit with no experimental data for the $Imma$ phase.
Here we use the data taken by (Kennedy, 1999) at 1023K.
The current structure can be a high-temperature ( e.g. SrZrO$_{3}$) or high-pressure (BaIrO$_{3}$) phase, depending on the compound.
We attempted to list the chemical formulas for the similar structures in the form ABC$_{3}$, where A is the (4b) Wyckoff position, (corresponding to the Ca site in cubic perovskite), B (4c) (Ti site) and C is (4a)\&(8h) (the oxygen site).
In addition, both the A (4b) and B (4c) sites are often alloyed, and even the (4a) and (8h) sites can be a mixture of oxygen and nitrogen.
$a \left(x_{4} + \frac{1}{2}\right) \,\mathbf{\hat{x}}- a x_{4} \,\mathbf{\hat{y}}$
(8h)
O II
References
B. J. Kennedy, C. J. Howard, and B. C. Chakoumakos, High-temperature phase transitions in SrZrO$_{3}$, Phys. Rev. B 56, 4023–4027 (1999), doi:10.1103/PhysRevB.59.4023.
A. Kumar, S. Kumari, H. Borkar, R. S. Katiyar, and J. F. Scott, Experimental verification of the {\em ab initio} phase transition sequence in SrZrO$_{3}$ and comparisons with SrHfO$_{3}$ and SrSnO$_{3}$, npj Comput. Mater. 3, 2 (2017), doi:10.1038/s41524-016-0002-y.
Q.-J. Liu, Z.-T. Liu, L.-P. Feng, and H. Tian, Study of structural, elastic, electronic and optical properties of seven SrZrO$_{3}$ phases: First-principles calculations, J. Solid State Chem. 196, 425–434 (2012), doi:10.1016/j.jssc.2012.07.005.
H. Fujimori, M. Kakihana, K. Ioku, S. Goto, and M. Yoshimura, Structural Phase Transitions between 700 and 850$^\\circ$C in SrZrO$_{3}$ Studied by Raman Spectroscopy, J. Ceramic Soc. Japan 112, 189–192 (2004), doi:10.2109/jcersj.112.189.
Found in
A. Kumar, S. Kumari, H. Borkar, R. S. K., and J. F. Scott, Experimental verification of the {\em ab initio} phase transition sequence in SrZrO$_{3}$ and comparisons with SrHfO$_{3}$ and SrSnO$_{3}$, npj Comput. Mater. 3, 2 (2017), doi:10.1038/s41524-016-0002-y.
First cited in
N. Anderson, M. J. Mehl, H. Eckert, S. Divilov, X. Campilongo, S. Curtarolo, The AFLOW Library of Crystallographic Prototypes: Part 5. Submitted to Computational Materials Science (2026).