γ-CuZrF$_{6}$ Structure: AB12C_aP14_2_b_6i_c-001
| Prototype | CuF$_{6}$Zr |
| AFLOW prototype label | AB12C_aP14_2_b_6i_c-001 |
| ICSD | 30117 |
| Pearson symbol | aP14 |
| Space group number | 2 |
| Space group symbol | $P\overline{1}$ |
| AFLOW prototype command |
aflow --proto=AB12C_aP14_2_b_6i_c-001
--params=$a, \allowbreak b/a, \allowbreak c/a, \allowbreak \alpha, \allowbreak \beta, \allowbreak \gamma, \allowbreak x_{3}, \allowbreak y_{3}, \allowbreak z_{3}, \allowbreak x_{4}, \allowbreak y_{4}, \allowbreak z_{4}, \allowbreak x_{5}, \allowbreak y_{5}, \allowbreak z_{5}, \allowbreak x_{6}, \allowbreak y_{6}, \allowbreak z_{6}, \allowbreak x_{7}, \allowbreak y_{7}, \allowbreak z_{7}, \allowbreak x_{8}, \allowbreak y_{8}, \allowbreak z_{8}$ |
- CuZrF$_{6}$ exists in four forms, depending on the temperature. Structures below 500K show evidence of a Jahn-Teller distortion.
- $\alpha'$–CuZrF$_{6}$ is the high temperature cubic form. Evidence from (Propach, 1978) shows this to be stable above $≈ 450$K. We use the lattice constant at 500K.
- $\alpha$–CuZrF$_{6}$ is stable above 383K. The fluorine (6f) sites are doubled, with only one of each pair occupied. We use data taken at 393K.
- $\beta$–CuZrF$_{6}$ is stable between 353 and 383K. In this case the Jahn-Teller distortion is locked in, so there are only six fluorine sites, all fully occupied.
- $\gamma$–CuZrF$_{6}$ (this structure) is stable below 353K. Again each fluorine site is only half-filled, but the ICSD entry only picks one site from each pair.
- The primitive vectors here are equivalent to, but substantially different from, those used by (Propach, 1978).
\[ \begin{array}{ccc}
\mathbf{a_{1}}&=&a \,\mathbf{\hat{x}}\\\mathbf{a_{2}}&=&b \cos{\gamma} \,\mathbf{\hat{x}}+b \sin{\gamma} \,\mathbf{\hat{y}}\\\mathbf{a_{3}}&=&c_{x} \,\mathbf{\hat{x}}+c_{y} \,\mathbf{\hat{y}}+c_{z} \,\mathbf{\hat{z}}\\c_{x} & = & c \cos{\beta} \\ c_{y} & = & c (\cos{\alpha} - \cos{\beta}\cos{\gamma}) / {\sin{\gamma}} \\ c_{z} & = & \sqrt{c^2 - c_{x}^2- c_{y}^2}
\end{array}\]
Basis vectors
| Lattice coordinates | Cartesian coordinates | Wyckoff position | Atom type | |||
|---|---|---|---|---|---|---|
| $\mathbf{B_{1}}$ | = | $\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}c_{x} \,\mathbf{\hat{x}}+\frac{1}{2}c_{y} \,\mathbf{\hat{y}}+\frac{1}{2}c_{z} \,\mathbf{\hat{z}}$ | (1b) | Cu I |
| $\mathbf{B_{2}}$ | = | $\frac{1}{2} \, \mathbf{a}_{2}$ | = | $\frac{1}{2}b \cos{\gamma} \,\mathbf{\hat{x}}+\frac{1}{2}b \sin{\gamma} \,\mathbf{\hat{y}}$ | (1c) | Zr I |
| $\mathbf{B_{3}}$ | = | $x_{3} \, \mathbf{a}_{1}+y_{3} \, \mathbf{a}_{2}+z_{3} \, \mathbf{a}_{3}$ | = | $\left(a x_{3} + b y_{3} \cos{\gamma} + c_{x} z_{3}\right) \,\mathbf{\hat{x}}+\left(b y_{3} \sin{\gamma} + c_{y} z_{3}\right) \,\mathbf{\hat{y}}+c_{z} z_{3} \,\mathbf{\hat{z}}$ | (2i) | F I |
| $\mathbf{B_{4}}$ | = | $- x_{3} \, \mathbf{a}_{1}- y_{3} \, \mathbf{a}_{2}- z_{3} \, \mathbf{a}_{3}$ | = | $- \left(a x_{3} + b y_{3} \cos{\gamma} + c_{x} z_{3}\right) \,\mathbf{\hat{x}}- \left(b y_{3} \sin{\gamma} + c_{y} z_{3}\right) \,\mathbf{\hat{y}}- c_{z} z_{3} \,\mathbf{\hat{z}}$ | (2i) | F I |
| $\mathbf{B_{5}}$ | = | $x_{4} \, \mathbf{a}_{1}+y_{4} \, \mathbf{a}_{2}+z_{4} \, \mathbf{a}_{3}$ | = | $\left(a x_{4} + b y_{4} \cos{\gamma} + c_{x} z_{4}\right) \,\mathbf{\hat{x}}+\left(b y_{4} \sin{\gamma} + c_{y} z_{4}\right) \,\mathbf{\hat{y}}+c_{z} z_{4} \,\mathbf{\hat{z}}$ | (2i) | F II |
| $\mathbf{B_{6}}$ | = | $- x_{4} \, \mathbf{a}_{1}- y_{4} \, \mathbf{a}_{2}- z_{4} \, \mathbf{a}_{3}$ | = | $- \left(a x_{4} + b y_{4} \cos{\gamma} + c_{x} z_{4}\right) \,\mathbf{\hat{x}}- \left(b y_{4} \sin{\gamma} + c_{y} z_{4}\right) \,\mathbf{\hat{y}}- c_{z} z_{4} \,\mathbf{\hat{z}}$ | (2i) | F II |
| $\mathbf{B_{7}}$ | = | $x_{5} \, \mathbf{a}_{1}+y_{5} \, \mathbf{a}_{2}+z_{5} \, \mathbf{a}_{3}$ | = | $\left(a x_{5} + b y_{5} \cos{\gamma} + c_{x} z_{5}\right) \,\mathbf{\hat{x}}+\left(b y_{5} \sin{\gamma} + c_{y} z_{5}\right) \,\mathbf{\hat{y}}+c_{z} z_{5} \,\mathbf{\hat{z}}$ | (2i) | F III |
| $\mathbf{B_{8}}$ | = | $- x_{5} \, \mathbf{a}_{1}- y_{5} \, \mathbf{a}_{2}- z_{5} \, \mathbf{a}_{3}$ | = | $- \left(a x_{5} + b y_{5} \cos{\gamma} + c_{x} z_{5}\right) \,\mathbf{\hat{x}}- \left(b y_{5} \sin{\gamma} + c_{y} z_{5}\right) \,\mathbf{\hat{y}}- c_{z} z_{5} \,\mathbf{\hat{z}}$ | (2i) | F III |
| $\mathbf{B_{9}}$ | = | $x_{6} \, \mathbf{a}_{1}+y_{6} \, \mathbf{a}_{2}+z_{6} \, \mathbf{a}_{3}$ | = | $\left(a x_{6} + b y_{6} \cos{\gamma} + c_{x} z_{6}\right) \,\mathbf{\hat{x}}+\left(b y_{6} \sin{\gamma} + c_{y} z_{6}\right) \,\mathbf{\hat{y}}+c_{z} z_{6} \,\mathbf{\hat{z}}$ | (2i) | F IV |
| $\mathbf{B_{10}}$ | = | $- x_{6} \, \mathbf{a}_{1}- y_{6} \, \mathbf{a}_{2}- z_{6} \, \mathbf{a}_{3}$ | = | $- \left(a x_{6} + b y_{6} \cos{\gamma} + c_{x} z_{6}\right) \,\mathbf{\hat{x}}- \left(b y_{6} \sin{\gamma} + c_{y} z_{6}\right) \,\mathbf{\hat{y}}- c_{z} z_{6} \,\mathbf{\hat{z}}$ | (2i) | F IV |
| $\mathbf{B_{11}}$ | = | $x_{7} \, \mathbf{a}_{1}+y_{7} \, \mathbf{a}_{2}+z_{7} \, \mathbf{a}_{3}$ | = | $\left(a x_{7} + b y_{7} \cos{\gamma} + c_{x} z_{7}\right) \,\mathbf{\hat{x}}+\left(b y_{7} \sin{\gamma} + c_{y} z_{7}\right) \,\mathbf{\hat{y}}+c_{z} z_{7} \,\mathbf{\hat{z}}$ | (2i) | F V |
| $\mathbf{B_{12}}$ | = | $- x_{7} \, \mathbf{a}_{1}- y_{7} \, \mathbf{a}_{2}- z_{7} \, \mathbf{a}_{3}$ | = | $- \left(a x_{7} + b y_{7} \cos{\gamma} + c_{x} z_{7}\right) \,\mathbf{\hat{x}}- \left(b y_{7} \sin{\gamma} + c_{y} z_{7}\right) \,\mathbf{\hat{y}}- c_{z} z_{7} \,\mathbf{\hat{z}}$ | (2i) | F V |
| $\mathbf{B_{13}}$ | = | $x_{8} \, \mathbf{a}_{1}+y_{8} \, \mathbf{a}_{2}+z_{8} \, \mathbf{a}_{3}$ | = | $\left(a x_{8} + b y_{8} \cos{\gamma} + c_{x} z_{8}\right) \,\mathbf{\hat{x}}+\left(b y_{8} \sin{\gamma} + c_{y} z_{8}\right) \,\mathbf{\hat{y}}+c_{z} z_{8} \,\mathbf{\hat{z}}$ | (2i) | F VI |
| $\mathbf{B_{14}}$ | = | $- x_{8} \, \mathbf{a}_{1}- y_{8} \, \mathbf{a}_{2}- z_{8} \, \mathbf{a}_{3}$ | = | $- \left(a x_{8} + b y_{8} \cos{\gamma} + c_{x} z_{8}\right) \,\mathbf{\hat{x}}- \left(b y_{8} \sin{\gamma} + c_{y} z_{8}\right) \,\mathbf{\hat{y}}- c_{z} z_{8} \,\mathbf{\hat{z}}$ | (2i) | F VI |
References
- V. Propach and F. Steffens, Über die Strukturen der CuZrF$_{6}$-Modifikationen - Neutronenbeugungsuntersuchungen an den Kristallpulvern, Z. Krystallogr. 33, 268–274 (1978), doi:10.1515/znb-1978-0304.
Prototype Generator
aflow --proto=AB12C_aP14_2_b_6i_c --params=$a,b/a,c/a,\alpha,\beta,\gamma,x_{3},y_{3},z_{3},x_{4},y_{4},z_{4},x_{5},y_{5},z_{5},x_{6},y_{6},z_{6},x_{7},y_{7},z_{7},x_{8},y_{8},z_{8}$