CeCr$_{2}$Si$_{2}$C Structure: ABC2D2_tP6_123_b_a_e_h-001
Other compounds with this structure
CsV$_{2}$Se$_{2}$O, DyCr$_{2}$Si$_{2}$C, GdCr$_{2}$Si$_{2}$C, HoCr$_{2}$Si$_{2}$C, LaCr$_{2}$Si$_{2}$C, NdCr$_{2}$Si$_{2}$C, PrCr$_{2}$Si$_{2}$C, SmCr$_{2}$Si$_{2}$C, TbCr$_{2}$Si$_{2}$C, UCr$_{2}$Si$_{2}$C, YCr$_{2}$Si$_{2}$C
- (Pohlkamp, 2001) refer to this as a
filled ThCr$_{2}$Si$_{2}$ structure.
- BaTi$_{2}$As$_{2}$O and CeCr$_{2}$Si$_{2}$C are both in space group $P4/mmm$ #123, and use the same Wyckoff positions. They differ in the c/a ratio. We follow the ICSD and put them into separate prototypes.
\[ \begin{array}{ccc}
\mathbf{a_{1}}&=&a \,\mathbf{\hat{x}}\\\mathbf{a_{2}}&=&a \,\mathbf{\hat{y}}\\\mathbf{a_{3}}&=&c \,\mathbf{\hat{z}}
\end{array}\]
Basis vectors
| Lattice coordinates | Cartesian coordinates | Wyckoff position | Atom type | |||
|---|---|---|---|---|---|---|
| $\mathbf{B_{1}}$ | = | $0$ | = | $0$ | (1a) | Ce I |
| $\mathbf{B_{2}}$ | = | $\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}c \,\mathbf{\hat{z}}$ | (1b) | C I |
| $\mathbf{B_{3}}$ | = | $\frac{1}{2} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}$ | (2e) | Cr I |
| $\mathbf{B_{4}}$ | = | $\frac{1}{2} \, \mathbf{a}_{1}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}c \,\mathbf{\hat{z}}$ | (2e) | Cr I |
| $\mathbf{B_{5}}$ | = | $\frac{1}{2} \, \mathbf{a}_{1}+\frac{1}{2} \, \mathbf{a}_{2}+z_{4} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}+c z_{4} \,\mathbf{\hat{z}}$ | (2h) | Si I |
| $\mathbf{B_{6}}$ | = | $\frac{1}{2} \, \mathbf{a}_{1}+\frac{1}{2} \, \mathbf{a}_{2}- z_{4} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}- c z_{4} \,\mathbf{\hat{z}}$ | (2h) | Si I |
References
- C. Tang, S. Fan, and M. Zhu, Structure and magnetic properties of CeCr$_{2}$Si$_{2}$C, J. Alloys Compd. 299, 1–4 (2000), doi:10.1016/S0925-8388(99)00631-3.
Found in
- M. W. Pohlkamp and W. Jeitschko, Preparation, Properties, and Crystal Structure of Quaternary Silicide Carbides RCr$_{2}$Si$_{2}$C (R = Y, La-Nd, Sm, Gd-Ho), Z. Naturforsch. B 56, 1143–1148 (2001), doi:10.1515/znb-2001-1108.
First cited in
- H. Eckert, S. Divilov, M. J. Mehl, D. Hicks, A. C. Zettel, M. Esters, X. Campilongo, and S. Curtarolo, The AFLOW Library of Crystallographic Prototypes: Part 4, Comp. Mat. Sci. 240, 112988 (2024). (doi=10.1016/j.commatsci.2021.110450)
Geometry files
Prototype Generator
aflow --proto=ABC2D2_tP6_123_b_a_e_h --params=$a,c/a,z_{4}$