β-SeTl ($B37$) Structure: AB_tI16_140_ab_h-001
| Prototype | SeTl |
| AFLOW prototype label | AB_tI16_140_ab_h-001 |
| Strukturbericht designation | $B37$ |
| ICSD | 30219 |
| Pearson symbol | tI16 |
| Space group number | 140 |
| Space group symbol | $I4/mcm$ |
| AFLOW prototype command |
aflow --proto=AB_tI16_140_ab_h-001
--params=$a, \allowbreak c/a, \allowbreak x_{3}$ |
Other compounds with this structure
InTe, STl, AlKTe$_{2}$, AlNaSe$_{2}$, AlNaTe$_{2}$, GaNaTe$_{2}$, GaTe$_{2}$Tl, InKTe$_{2}$, InNaTe$_{2}$, InS$_{2}$Te
- When $c=a$ and $x=1/4$ the atoms are at the positions of the body-centered cubic (A2) lattice.
- (Okamoto, 2011) identifies this as $\beta$–SeTl, stable from 188$^\circ$C to the melting point at approximately 350$^\circ$C. No crystallographic information on the ground-state $\alpha$ phase has been found.
- The lattice constants presented here are from (Yadav, 1976), while the atomic positions and the ICSD entry are from (Ketelaar, 1939).
\[ \begin{array}{ccc}
\mathbf{a_{1}}&=&- \frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}\\\mathbf{a_{2}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}- \frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}\\\mathbf{a_{3}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}- \frac{1}{2}c \,\mathbf{\hat{z}}
\end{array}\]
Basis vectors
| Lattice coordinates | Cartesian coordinates | Wyckoff position | Atom type | |||
|---|---|---|---|---|---|---|
| $\mathbf{B_{1}}$ | = | $\frac{1}{4} \, \mathbf{a}_{1}+\frac{1}{4} \, \mathbf{a}_{2}$ | = | $\frac{1}{4}c \,\mathbf{\hat{z}}$ | (4a) | Se I |
| $\mathbf{B_{2}}$ | = | $\frac{3}{4} \, \mathbf{a}_{1}+\frac{3}{4} \, \mathbf{a}_{2}$ | = | $\frac{3}{4}c \,\mathbf{\hat{z}}$ | (4a) | Se I |
| $\mathbf{B_{3}}$ | = | $\frac{3}{4} \, \mathbf{a}_{1}+\frac{1}{4} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{4}c \,\mathbf{\hat{z}}$ | (4b) | Se II |
| $\mathbf{B_{4}}$ | = | $\frac{1}{4} \, \mathbf{a}_{1}+\frac{3}{4} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{4}c \,\mathbf{\hat{z}}$ | (4b) | Se II |
| $\mathbf{B_{5}}$ | = | $\left(x_{3} + \frac{1}{2}\right) \, \mathbf{a}_{1}+x_{3} \, \mathbf{a}_{2}+\left(2 x_{3} + \frac{1}{2}\right) \, \mathbf{a}_{3}$ | = | $a x_{3} \,\mathbf{\hat{x}}+a \left(x_{3} + \frac{1}{2}\right) \,\mathbf{\hat{y}}$ | (8h) | Tl I |
| $\mathbf{B_{6}}$ | = | $- \left(x_{3} - \frac{1}{2}\right) \, \mathbf{a}_{1}- x_{3} \, \mathbf{a}_{2}- \left(2 x_{3} - \frac{1}{2}\right) \, \mathbf{a}_{3}$ | = | $- a x_{3} \,\mathbf{\hat{x}}- a \left(x_{3} - \frac{1}{2}\right) \,\mathbf{\hat{y}}$ | (8h) | Tl I |
| $\mathbf{B_{7}}$ | = | $x_{3} \, \mathbf{a}_{1}- \left(x_{3} - \frac{1}{2}\right) \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $- a \left(x_{3} - \frac{1}{2}\right) \,\mathbf{\hat{x}}+a x_{3} \,\mathbf{\hat{y}}$ | (8h) | Tl I |
| $\mathbf{B_{8}}$ | = | $- x_{3} \, \mathbf{a}_{1}+\left(x_{3} + \frac{1}{2}\right) \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $a \left(x_{3} + \frac{1}{2}\right) \,\mathbf{\hat{x}}- a x_{3} \,\mathbf{\hat{y}}$ | (8h) | Tl I |
References
- J. A. A. Ketelaar, W. H. t'Hart, M. Moerel, and D. Polder, The Crystal Structure of TlSe, Thallous Thallic or Thallosic Selenide, Z. Krystallogr. 101, 396–406 (1939), doi:10.1524/zkri.1939.101.1.396.
- R. Yadav, R. P. Ram, and S. Bhan, On the Thallium-Selenium-Tellurium System, Z. Metallkd. 67, 173–177 (1976), doi:10.1515/ijmr-1976-670308.
- H. Okamoto, Se-Tl (Selenium-Thallium), J. Phase Eq. Diff. 32, 570–571 (2011), doi:10.1007/s11669-011-9954-2.
Found in
- P. Villars, TlSe Crystal Structure (2016). PAULING FILE in: Inorganic Solid Phases, SpringerMaterials (online database), Springer, Heidelberg (ed.) SpringerMaterials.
Prototype Generator
aflow --proto=AB_tI16_140_ab_h --params=$a,c/a,x_{3}$