TlCo$_{2}$S$_{2}$ Structure: A2B2C_tI10_139_d_e_a-002
| Prototype | Co$_{2}$S$_{2}$Tl |
| AFLOW prototype label | A2B2C_tI10_139_d_e_a-002 |
| ICSD | 100438 |
| Pearson symbol | tI10 |
| Space group number | 139 |
| Space group symbol | $I4/mmm$ |
| AFLOW prototype command |
aflow --proto=A2B2C_tI10_139_d_e_a-002
--params=$a, \allowbreak c/a, \allowbreak z_{3}$ |
Other compounds with this structure
BaCr$_{2}$As$_{2}$, BaFe$_{2}$As$_{2}$, BaMn$_{2}$Bi$_{2}$, BaP$_{2}$Zn$_{2}$, BaSr$_{2}$As$_{2}$, BaCo$_{2}$As$_{2}$, BiCe$_{2}$O$_{2}$, BiTh$_{2}$N$_{2}$, BiU$_{2}$N$_{2}$, CaCo$_{2}$As$_{2}$, SrCo$_{2}$As$_{2}$, EuCo$_{2}$As$_{2}$, EuFe$4_{2}$As$_{2}$, CsCo$_{2}$Se$_{2}$, KCo$_{2}$As$_{2}$, KCo$_{2}$P$_{2}$, KCo$_{2}$Se$_{2}$, KFe$_{2}$As$_{2}$, KFe$_{2}$P$_{2}$, KRh$_{2}$As$_{2}$, KRh$_{2}$P$_{2}$, RbCo$_{2}$Se$_{2}$, RbFe$_{2}$As$_{2}$, RbNi$_{2}$Se$_{2}$, SbTh$_{2}$N$_{2}$, SbU$_{2}$N$_{2}$, SeBi$_{2}$O$_{2}$, SeBi$_{2}$O$_{2}$, TeBi$_{2}$O$_{2}$, TeCe$_{2}$O$_{2}$, TeDy$_{2}$O$_{2}$, TeEr$_{2}$O$_{2}$, TeLu$_{2}$O$_{2}$, TeTb$_{2}$O$_{2}$, TeY$_{2}$O$_{2}$, TeTh$_{2}$N$_{2}$, TeU$_{2}$N$_{2}$, TlCo$_{2}$Se$_{2}$, TlCu$_{2}$S$_{2}$, TlCu$_{2}$Se$_{2}$, TlCu$_{2}$Te$_{2}$, TlFe$_{2}$S$_{2}$, TlFe$_{2}$Se$_{2}$, TlNi$_{2}$S$_{2}$, TlNi$_{2}$Se$_{2}$, Cl(Li$_{0.25}$Be$_{0.75}$)$_{2}$O$_{2}$, Cl(Na$_{0.25}$Be$_{0.75}$)$_{2}$O$_{2}$, EuFe$_{2}$(As$_{0.8}$P$_{0.2}$)$_{2}$
- This is a ternary form of the $D1_{3}$ (BaAl$_{4}$) structure. It differs from the ThCr$_{2}$Si$_{2}$ structure in that here $c/a > 3$.
- Other authors designate TlCu$_{2}$Se$_{2}$ or Cl(Li$_{0.25}$Be$_{0.75}$)$_{2}$O$_{2}$ as the prototype for this structure, but (Klepp, 1978) give complete structural information for TlCo$_{2}$S$_{2}$, so we use that as the prototype.
\[ \begin{array}{ccc}
\mathbf{a_{1}}&=&- \frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}\\\mathbf{a_{2}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}- \frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}\\\mathbf{a_{3}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}- \frac{1}{2}c \,\mathbf{\hat{z}}
\end{array}\]
Basis vectors
| Lattice coordinates | Cartesian coordinates | Wyckoff position | Atom type | |||
|---|---|---|---|---|---|---|
| $\mathbf{B_{1}}$ | = | $0$ | = | $0$ | (2a) | Tl I |
| $\mathbf{B_{2}}$ | = | $\frac{3}{4} \, \mathbf{a}_{1}+\frac{1}{4} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{4}c \,\mathbf{\hat{z}}$ | (4d) | Co I |
| $\mathbf{B_{3}}$ | = | $\frac{1}{4} \, \mathbf{a}_{1}+\frac{3}{4} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{4}c \,\mathbf{\hat{z}}$ | (4d) | Co I |
| $\mathbf{B_{4}}$ | = | $z_{3} \, \mathbf{a}_{1}+z_{3} \, \mathbf{a}_{2}$ | = | $c z_{3} \,\mathbf{\hat{z}}$ | (4e) | S I |
| $\mathbf{B_{5}}$ | = | $- z_{3} \, \mathbf{a}_{1}- z_{3} \, \mathbf{a}_{2}$ | = | $- c z_{3} \,\mathbf{\hat{z}}$ | (4e) | S I |
References
- K. Klepp and H. Boller, Ternäre Thallium-Übergangsmetall-Chalkogenide mit ThCr$_{2}$Si$_{2}$-Struktur, Monatsh. Chem. 109, 1049–1057 (1978), doi:10.1007/BF00913007.
Found in
- R. Berger and C. F. van Bruggen, TlCu$_{2}$Se$_{2}$: A p-type metal with a layer structure, J. Less-Common Met. 99, 113–123 (1984), doi:10.1016/0022-5088(84)90340-0.
Prototype Generator
aflow --proto=A2B2C_tI10_139_d_e_a --params=$a,c/a,z_{3}$