δ-CuTi ($L2_{a}$) Structure: AB_tP2_123_a_d-002
| Prototype | CuTi |
| AFLOW prototype label | AB_tP2_123_a_d-002 |
| Strukturbericht designation | $L2_{a}$ |
| ICSD | 103127 |
| Pearson symbol | tP2 |
| Space group number | 123 |
| Space group symbol | $P4/mmm$ |
| AFLOW prototype command |
aflow --proto=AB_tP2_123_a_d-002
--params=$a, \allowbreak c/a$ |
Other compounds with this structure
HgMn
- As we have been unable to find a copy of (Karlsson, 1951), we obtained the value a = 4.44Å from (Pearson, 1958). The ICSD entry uses a = 3.14Å, referencing the original publication. For now we will continue to use the value from (Pearson, 1958).
- This structure has the same AFLOW designation, AB_tP2_123_a_d, as CuAu ($L1_{0}$). The only difference in the structures is the c/a ratio. $L1_{0}$ has $c/a ≈ \sqrt{2}$, characteristic of face-centered cubic ordering, while $L2_{a}$ has $c/a ≈ 1$, a body-centered cubic-like system.
\[ \begin{array}{ccc}
\mathbf{a_{1}}&=&a \,\mathbf{\hat{x}}\\\mathbf{a_{2}}&=&a \,\mathbf{\hat{y}}\\\mathbf{a_{3}}&=&c \,\mathbf{\hat{z}}
\end{array}\]
Basis vectors
| Lattice coordinates | Cartesian coordinates | Wyckoff position | Atom type | |||
|---|---|---|---|---|---|---|
| $\mathbf{B_{1}}$ | = | $0$ | = | $0$ | (1a) | Cu I |
| $\mathbf{B_{2}}$ | = | $\frac{1}{2} \, \mathbf{a}_{1}+\frac{1}{2} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}$ | (1d) | Ti I |
References
- N. Karlsson, An X-Ray Study of the Phases in the Copper-Titanium System, J. Inst. Met. 79, 391–405 (1951).
Found in
- W. B. Pearson, A Handbook of Lattice Spacings and Structures of Metals and Alloys, International Series of Monographs on Metal Physics and Physical Metallurgy, vol. 4 (Pergamon Press, Oxford, London, Edinburgh, New York, Paris, Frankfort, 1958), 1964 reprint with corrections edn.
Prototype Generator
aflow --proto=AB_tP2_123_a_d --params=$a,c/a$