SrLa$_{2}$Sc$_{2}$O$_{7}$ Structure: A2B7C2D_oF48_69_g_agl_g_b-001
| Prototype | La$_{2}$O$_{7}$Sc$_{2}$Sr |
| AFLOW prototype label | A2B7C2D_oF48_69_g_agl_g_b-001 |
| ICSD | 67625 |
| CCDC | 1629606 |
| Pearson symbol | oF48 |
| Space group number | 69 |
| Space group symbol | $Fmmm$ |
| AFLOW prototype command |
aflow --proto=A2B7C2D_oF48_69_g_agl_g_b-001
--params=$a, \allowbreak b/a, \allowbreak c/a, \allowbreak x_{3}, \allowbreak x_{4}, \allowbreak x_{5}, \allowbreak x_{6}$ |
Other compounds with this structure
BaEu$_{2}$Mn$_{2}$O$_{7}$, BaMn$_{2}$Nd$_{2}$O$_{7}$, CaLi$_{2}$Ta$_{2}$O$_{7}$, SrLi$_{2}$Nb$_{2}$O$_{7}$, SrEu$_{2}$Sc$_{2}$O$_{7}$, SrGd$_{2}$Sc$_{2}$O$_{7}$, SrNd$_{2}$Sc$_{2}$O$_{7}$, SrPr$_{2}$Sc$_{2}$O$_{7}$, SrSm$_{2}$Sc$_{2}$O$_{7}$, SrTb$_{2}$Sc$_{2}$O$_{7}$
- This is a Ruddlesden-Popper structure.
- AFLOW rotates the lattice vectors by 90$^\circ$ about the y-axis, interchanging the x- and z- directions.
- The site we label Sr I (4b) is actually 50% strontium and 50% lanthanum, while the site labeled La I (8g) is 75% lanthanum and 25% strontium.
- La$_{3}$Ni$_{2}$O$_{7}$ is a ternary form of this structure.
\[ \begin{array}{ccc}
\mathbf{a_{1}}&=&\frac{1}{2}b \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}\\\mathbf{a_{2}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}c \,\mathbf{\hat{z}}\\\mathbf{a_{3}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}b \,\mathbf{\hat{y}}
\end{array}\]
Basis vectors
| Lattice coordinates | Cartesian coordinates | Wyckoff position | Atom type | |||
|---|---|---|---|---|---|---|
| $\mathbf{B_{1}}$ | = | $0$ | = | $0$ | (4a) | O I |
| $\mathbf{B_{2}}$ | = | $\frac{1}{2} \, \mathbf{a}_{1}+\frac{1}{2} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ | = | $\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}b \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}$ | (4b) | Sr I |
| $\mathbf{B_{3}}$ | = | $- x_{3} \, \mathbf{a}_{1}+x_{3} \, \mathbf{a}_{2}+x_{3} \, \mathbf{a}_{3}$ | = | $a x_{3} \,\mathbf{\hat{x}}$ | (8g) | La I |
| $\mathbf{B_{4}}$ | = | $x_{3} \, \mathbf{a}_{1}- x_{3} \, \mathbf{a}_{2}- x_{3} \, \mathbf{a}_{3}$ | = | $- a x_{3} \,\mathbf{\hat{x}}$ | (8g) | La I |
| $\mathbf{B_{5}}$ | = | $- x_{4} \, \mathbf{a}_{1}+x_{4} \, \mathbf{a}_{2}+x_{4} \, \mathbf{a}_{3}$ | = | $a x_{4} \,\mathbf{\hat{x}}$ | (8g) | O II |
| $\mathbf{B_{6}}$ | = | $x_{4} \, \mathbf{a}_{1}- x_{4} \, \mathbf{a}_{2}- x_{4} \, \mathbf{a}_{3}$ | = | $- a x_{4} \,\mathbf{\hat{x}}$ | (8g) | O II |
| $\mathbf{B_{7}}$ | = | $- x_{5} \, \mathbf{a}_{1}+x_{5} \, \mathbf{a}_{2}+x_{5} \, \mathbf{a}_{3}$ | = | $a x_{5} \,\mathbf{\hat{x}}$ | (8g) | Sc I |
| $\mathbf{B_{8}}$ | = | $x_{5} \, \mathbf{a}_{1}- x_{5} \, \mathbf{a}_{2}- x_{5} \, \mathbf{a}_{3}$ | = | $- a x_{5} \,\mathbf{\hat{x}}$ | (8g) | Sc I |
| $\mathbf{B_{9}}$ | = | $- \left(x_{6} - \frac{1}{2}\right) \, \mathbf{a}_{1}+x_{6} \, \mathbf{a}_{2}+x_{6} \, \mathbf{a}_{3}$ | = | $a x_{6} \,\mathbf{\hat{x}}+\frac{1}{4}b \,\mathbf{\hat{y}}+\frac{1}{4}c \,\mathbf{\hat{z}}$ | (16l) | O III |
| $\mathbf{B_{10}}$ | = | $x_{6} \, \mathbf{a}_{1}- \left(x_{6} - \frac{1}{2}\right) \, \mathbf{a}_{2}- \left(x_{6} - \frac{1}{2}\right) \, \mathbf{a}_{3}$ | = | $- a \left(x_{6} - \frac{1}{2}\right) \,\mathbf{\hat{x}}+\frac{1}{4}b \,\mathbf{\hat{y}}+\frac{1}{4}c \,\mathbf{\hat{z}}$ | (16l) | O III |
| $\mathbf{B_{11}}$ | = | $\left(x_{6} + \frac{1}{2}\right) \, \mathbf{a}_{1}- x_{6} \, \mathbf{a}_{2}- x_{6} \, \mathbf{a}_{3}$ | = | $- a x_{6} \,\mathbf{\hat{x}}+\frac{1}{4}b \,\mathbf{\hat{y}}+\frac{1}{4}c \,\mathbf{\hat{z}}$ | (16l) | O III |
| $\mathbf{B_{12}}$ | = | $- x_{6} \, \mathbf{a}_{1}+\left(x_{6} + \frac{1}{2}\right) \, \mathbf{a}_{2}+\left(x_{6} + \frac{1}{2}\right) \, \mathbf{a}_{3}$ | = | $a \left(x_{6} + \frac{1}{2}\right) \,\mathbf{\hat{x}}+\frac{1}{4}b \,\mathbf{\hat{y}}+\frac{1}{4}c \,\mathbf{\hat{z}}$ | (16l) | O III |
References
- I.-S. Kim, H. Kawaji, M. Itoh, and T. Nakamura, Structural and dielectric studies on the new series of layered compounds, strontium lanthanum scandium oxides, Mater. Res. Bull. 27, 1193–1203 (1992), doi:10.1016/0025-5408(92)90227-Q.
Found in
- R. Cao, X. Ouyang, Y. Jiao, X. Wang, Q. Hu, T. Chen, C. Liao, and Y. Li, Deep-red-emitting SrLa$_{2}$Sc$_{2}$O$_{7}$:Mn$^{4+}$ phosphor: Synthesis and photoluminescence properties, J. Alloys Compd. 795, 134–140 (2019), doi:10.1016/j.jallcom.2019.04.220. This paper actually references ICSD entry 67625, leading us to the (Kim, 1992) reference.
First cited in
- N. Anderson, M. J. Mehl, H. Eckert, S. Divilov, X. Campilongo, S. Curtarolo, The AFLOW Library of Crystallographic Prototypes: Part 5. Submitted to Computational Materials Science (2026).
Geometry files
Prototype Generator
aflow --proto=A2B7C2D_oF48_69_g_agl_g_b --params=$a,b/a,c/a,x_{3},x_{4},x_{5},x_{6}$