High Pressure Phase II (CH$_{3}$)(NH$_{3})$PbBr$_{3}$ Structure: A6B3C3D2_cI56_204_g_d_e_c-001
| Prototype | Br$_{3}$(CH$_{3}$)(NH$_{3}$)Pb |
| AFLOW prototype label | A6B3C3D2_cI56_204_g_d_e_c-001 |
| ICSD | 252416 |
| CCDC | 1446530 |
| Pearson symbol | cI56 |
| Space group number | 204 |
| Space group symbol | $Im\overline{3}$ |
| AFLOW prototype command |
aflow --proto=A6B3C3D2_cI56_204_g_d_e_c-001
--params=$a, \allowbreak x_{2}, \allowbreak x_{3}, \allowbreak y_{4}, \allowbreak z_{4}$ |
- CH$_{3}$NH$_{3}$PbBr$_{3}$ can be found in a variety of distorted perovskite ($E2_{1}$) structures, depending upon the temperature and pressure (Abia, 2022; Liang, 2023):
- A low temperature orthorhombic structure, stable below 145K.
- This intermediate temperature body-centered orthorhombic structure, stable from 145-157K.
- An intermediate temperature tetragonal structure, stable from 156-229K.
- The room-temperature cubic perovskite-like structure, stable above 229K.
- A cubic high-pressure Phase II structure, stable from 0.9-1.8 GPa.
- An orthorhombic Phase III structure, stable from 1.8-4.6 GPa.
- Another orthorhombic Phase IV structure was found by (Liang, 2023), but the atomic positions have yet to be calculated.
- This structure was determined at 1.7GPa and 296K.
- (Jaffe, 2016) do not report the positions of the hydrogen atoms. We assume the species we label
C
andN
are actually CH$_{3}$ and NH$_{3}$ radicals. - The (12d) site, which we label as carbon and is shown as a C-C dumbbell in the figures, is actually 41.667% (5/12) CH$_{3}$ radicals, 41.667 NH$_{3}$ radicals, and 16.667 (1/12) vacancies.
- The (12e) site, which we label as nitrogen and is shown as a nitrogen octahedron, is actually 25% CH$_{3}$, 25% NH$_{3}$, and 50% vacancies.
- The alternating (12d) and (12e) sites produce a double-perovskite, in contrast to the
simple
perovskites of the ambient pressure phases.
\[ \begin{array}{ccc}
\mathbf{a_{1}}&=&- \frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}a \,\mathbf{\hat{z}}\\\mathbf{a_{2}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}- \frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}a \,\mathbf{\hat{z}}\\\mathbf{a_{3}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}- \frac{1}{2}a \,\mathbf{\hat{z}}
\end{array}\]
Basis vectors
| Lattice coordinates | Cartesian coordinates | Wyckoff position | Atom type | |||
|---|---|---|---|---|---|---|
| $\mathbf{B_{1}}$ | = | $\frac{1}{2} \, \mathbf{a}_{1}+\frac{1}{2} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{4}a \,\mathbf{\hat{x}}+\frac{1}{4}a \,\mathbf{\hat{y}}+\frac{1}{4}a \,\mathbf{\hat{z}}$ | (8c) | Pb I |
| $\mathbf{B_{2}}$ | = | $\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{4}a \,\mathbf{\hat{x}}+\frac{1}{4}a \,\mathbf{\hat{y}}- \frac{1}{4}a \,\mathbf{\hat{z}}$ | (8c) | Pb I |
| $\mathbf{B_{3}}$ | = | $\frac{1}{2} \, \mathbf{a}_{2}$ | = | $\frac{1}{4}a \,\mathbf{\hat{x}}- \frac{1}{4}a \,\mathbf{\hat{y}}+\frac{1}{4}a \,\mathbf{\hat{z}}$ | (8c) | Pb I |
| $\mathbf{B_{4}}$ | = | $\frac{1}{2} \, \mathbf{a}_{1}$ | = | $- \frac{1}{4}a \,\mathbf{\hat{x}}+\frac{1}{4}a \,\mathbf{\hat{y}}+\frac{1}{4}a \,\mathbf{\hat{z}}$ | (8c) | Pb I |
| $\mathbf{B_{5}}$ | = | $x_{2} \, \mathbf{a}_{2}+x_{2} \, \mathbf{a}_{3}$ | = | $a x_{2} \,\mathbf{\hat{x}}$ | (12d) | C I |
| $\mathbf{B_{6}}$ | = | $- x_{2} \, \mathbf{a}_{2}- x_{2} \, \mathbf{a}_{3}$ | = | $- a x_{2} \,\mathbf{\hat{x}}$ | (12d) | C I |
| $\mathbf{B_{7}}$ | = | $x_{2} \, \mathbf{a}_{1}+x_{2} \, \mathbf{a}_{3}$ | = | $a x_{2} \,\mathbf{\hat{y}}$ | (12d) | C I |
| $\mathbf{B_{8}}$ | = | $- x_{2} \, \mathbf{a}_{1}- x_{2} \, \mathbf{a}_{3}$ | = | $- a x_{2} \,\mathbf{\hat{y}}$ | (12d) | C I |
| $\mathbf{B_{9}}$ | = | $x_{2} \, \mathbf{a}_{1}+x_{2} \, \mathbf{a}_{2}$ | = | $a x_{2} \,\mathbf{\hat{z}}$ | (12d) | C I |
| $\mathbf{B_{10}}$ | = | $- x_{2} \, \mathbf{a}_{1}- x_{2} \, \mathbf{a}_{2}$ | = | $- a x_{2} \,\mathbf{\hat{z}}$ | (12d) | C I |
| $\mathbf{B_{11}}$ | = | $\frac{1}{2} \, \mathbf{a}_{1}+\left(x_{3} + \frac{1}{2}\right) \, \mathbf{a}_{2}+x_{3} \, \mathbf{a}_{3}$ | = | $a x_{3} \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{z}}$ | (12e) | N I |
| $\mathbf{B_{12}}$ | = | $\frac{1}{2} \, \mathbf{a}_{1}- \left(x_{3} - \frac{1}{2}\right) \, \mathbf{a}_{2}- x_{3} \, \mathbf{a}_{3}$ | = | $- a x_{3} \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{z}}$ | (12e) | N I |
| $\mathbf{B_{13}}$ | = | $x_{3} \, \mathbf{a}_{1}+\frac{1}{2} \, \mathbf{a}_{2}+\left(x_{3} + \frac{1}{2}\right) \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{x}}+a x_{3} \,\mathbf{\hat{y}}$ | (12e) | N I |
| $\mathbf{B_{14}}$ | = | $- x_{3} \, \mathbf{a}_{1}+\frac{1}{2} \, \mathbf{a}_{2}- \left(x_{3} - \frac{1}{2}\right) \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{x}}- a x_{3} \,\mathbf{\hat{y}}$ | (12e) | N I |
| $\mathbf{B_{15}}$ | = | $\left(x_{3} + \frac{1}{2}\right) \, \mathbf{a}_{1}+x_{3} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{y}}+a x_{3} \,\mathbf{\hat{z}}$ | (12e) | N I |
| $\mathbf{B_{16}}$ | = | $- \left(x_{3} - \frac{1}{2}\right) \, \mathbf{a}_{1}- x_{3} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{y}}- a x_{3} \,\mathbf{\hat{z}}$ | (12e) | N I |
| $\mathbf{B_{17}}$ | = | $\left(y_{4} + z_{4}\right) \, \mathbf{a}_{1}+z_{4} \, \mathbf{a}_{2}+y_{4} \, \mathbf{a}_{3}$ | = | $a y_{4} \,\mathbf{\hat{y}}+a z_{4} \,\mathbf{\hat{z}}$ | (24g) | Br I |
| $\mathbf{B_{18}}$ | = | $- \left(y_{4} - z_{4}\right) \, \mathbf{a}_{1}+z_{4} \, \mathbf{a}_{2}- y_{4} \, \mathbf{a}_{3}$ | = | $- a y_{4} \,\mathbf{\hat{y}}+a z_{4} \,\mathbf{\hat{z}}$ | (24g) | Br I |
| $\mathbf{B_{19}}$ | = | $\left(y_{4} - z_{4}\right) \, \mathbf{a}_{1}- z_{4} \, \mathbf{a}_{2}+y_{4} \, \mathbf{a}_{3}$ | = | $a y_{4} \,\mathbf{\hat{y}}- a z_{4} \,\mathbf{\hat{z}}$ | (24g) | Br I |
| $\mathbf{B_{20}}$ | = | $- \left(y_{4} + z_{4}\right) \, \mathbf{a}_{1}- z_{4} \, \mathbf{a}_{2}- y_{4} \, \mathbf{a}_{3}$ | = | $- a y_{4} \,\mathbf{\hat{y}}- a z_{4} \,\mathbf{\hat{z}}$ | (24g) | Br I |
| $\mathbf{B_{21}}$ | = | $y_{4} \, \mathbf{a}_{1}+\left(y_{4} + z_{4}\right) \, \mathbf{a}_{2}+z_{4} \, \mathbf{a}_{3}$ | = | $a z_{4} \,\mathbf{\hat{x}}+a y_{4} \,\mathbf{\hat{z}}$ | (24g) | Br I |
| $\mathbf{B_{22}}$ | = | $- y_{4} \, \mathbf{a}_{1}- \left(y_{4} - z_{4}\right) \, \mathbf{a}_{2}+z_{4} \, \mathbf{a}_{3}$ | = | $a z_{4} \,\mathbf{\hat{x}}- a y_{4} \,\mathbf{\hat{z}}$ | (24g) | Br I |
| $\mathbf{B_{23}}$ | = | $y_{4} \, \mathbf{a}_{1}+\left(y_{4} - z_{4}\right) \, \mathbf{a}_{2}- z_{4} \, \mathbf{a}_{3}$ | = | $- a z_{4} \,\mathbf{\hat{x}}+a y_{4} \,\mathbf{\hat{z}}$ | (24g) | Br I |
| $\mathbf{B_{24}}$ | = | $- y_{4} \, \mathbf{a}_{1}- \left(y_{4} + z_{4}\right) \, \mathbf{a}_{2}- z_{4} \, \mathbf{a}_{3}$ | = | $- a z_{4} \,\mathbf{\hat{x}}- a y_{4} \,\mathbf{\hat{z}}$ | (24g) | Br I |
| $\mathbf{B_{25}}$ | = | $z_{4} \, \mathbf{a}_{1}+y_{4} \, \mathbf{a}_{2}+\left(y_{4} + z_{4}\right) \, \mathbf{a}_{3}$ | = | $a y_{4} \,\mathbf{\hat{x}}+a z_{4} \,\mathbf{\hat{y}}$ | (24g) | Br I |
| $\mathbf{B_{26}}$ | = | $z_{4} \, \mathbf{a}_{1}- y_{4} \, \mathbf{a}_{2}- \left(y_{4} - z_{4}\right) \, \mathbf{a}_{3}$ | = | $- a y_{4} \,\mathbf{\hat{x}}+a z_{4} \,\mathbf{\hat{y}}$ | (24g) | Br I |
| $\mathbf{B_{27}}$ | = | $- z_{4} \, \mathbf{a}_{1}+y_{4} \, \mathbf{a}_{2}+\left(y_{4} - z_{4}\right) \, \mathbf{a}_{3}$ | = | $a y_{4} \,\mathbf{\hat{x}}- a z_{4} \,\mathbf{\hat{y}}$ | (24g) | Br I |
| $\mathbf{B_{28}}$ | = | $- z_{4} \, \mathbf{a}_{1}- y_{4} \, \mathbf{a}_{2}- \left(y_{4} + z_{4}\right) \, \mathbf{a}_{3}$ | = | $- a y_{4} \,\mathbf{\hat{x}}- a z_{4} \,\mathbf{\hat{y}}$ | (24g) | Br I |
References
- A. Jaffe, Y. Lin, C. M. Beavers, J. Voss, W. L. Mao, and H. I. Karunadasa, High-Pressure Single-Crystal Structures of 3D Lead-Halide Hybrid Perovskites and Pressure Effects on their Electronic and Optical Properties}, ACS Cent. Sci. 2, 201–209 (2016), doi:10.1021/acscentsci.6b00055.
- C. Abia, C. A. López, L. C. {nadillas Delgado, M. T. Fernández-Diaz, and J. A. Alonso, Crystal structure thermal evolution and novel orthorhombic phase of methylammonium lead bromide, CH$_{3}$NH$_{3}$PbBr$_{3}$, Sci. Rep. 12, 18647 (2022), doi:10.1038/s41598-022-21544-2.
- A. Liang, R. Turnbull, C. Popescu, I. Fernandez-Guillen, R. Abargues, P. P. Boix, and D. Errandonea, Pressure-Induced Phase Transition versus Amorphization in Hybrid Methylammonium Lead Bromide Perovskite, J. Phys. Chem. C 127, 12821–12826 (2023), doi:10.1021/acs.jpcc.3c03263.
Found in
- A. Liang, R. Turnbull, C. Popescu, I. Fernandez-Guillen, R. Abargues, P. P. Boix, and D. Errandonea, Pressure-Induced Phase Transition versus Amorphization in Hybrid Methylammonium Lead Bromide Perovskite, J. Phys. Chem. C 127, 12821–12826 (2023), doi:10.1021/acs.jpcc.3c03263.
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).
Geometry files
Prototype Generator
aflow --proto=A6B3C3D2_cI56_204_g_d_e_c --params=$a,x_{2},x_{3},y_{4},z_{4}$