Encyclopedia of Crystallographic Prototypes

AFLOW Prototype: A2BC_oC16_63_f_c_c-002

This structure originally had the label A2BC_oC16_63_f_c_c. Calls to that address will be redirected here.

If you are using this page, please cite:
D. Hicks, M.J. Mehl, M. Esters, C. Oses, O. Levy, G.L.W. Hart, C. Toher, and S. Curtarolo, The AFLOW Library of Crystallographic Prototypes: Part 3, Comp. Mat. Sci. 199, 110450 (2021). (doi=10.1016/j.commatsci.2021.110450)

Links to this page

https://aflow.org/p/ECJE
or https://aflow.org/p/A2BC_oC16_63_f_c_c-002
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MgCuAl$_{2}$ ($E1_{a}$) Structure: A2BC_oC16_63_f_c_c-002

Picture of Structure; Click for Big Picture
Prototype Al$_{2}$CuMg
AFLOW prototype label A2BC_oC16_63_f_c_c-002
Strukturbericht designation $E1_{a}$
ICSD 415062
Pearson symbol oC16
Space group number 63
Space group symbol $Cmcm$
AFLOW prototype command aflow --proto=A2BC_oC16_63_f_c_c-002
--params=$a, \allowbreak b/a, \allowbreak c/a, \allowbreak y_{1}, \allowbreak y_{2}, \allowbreak y_{3}, \allowbreak z_{3}$

Other compounds with this structure

CaNiGa$_{2}$,  CeCuPd$_{2}$,  EuIrSn$_{2}$,  EuPdIn$_{2}$,  EuPdSn$_{2}$,  LaPdIn$_{2}$,  NdCuPd$_{2}$,  PPdNi$_{2}$,  PdSrMg$_{2}$,  PrCuPd$_{2}$,  ScNiAl$_{2}$,  SmCuPd$_{2}$,  TaBCo$_{2}$,  YNiAl$_{2}$,  YbAuIn$_{2}$,  YbPdIn$_{2}$


  • This is often referred to as an S-phase precipitate. It can be considered as the ternary version of the Re$_{3}$B structure.

\[ \begin{array}{ccc} \mathbf{a_{1}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}- \frac{1}{2}b \,\mathbf{\hat{y}}\\\mathbf{a_{2}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}b \,\mathbf{\hat{y}}\\\mathbf{a_{3}}&=&c \,\mathbf{\hat{z}} \end{array}\]

Basis vectors

Lattice coordinates Cartesian coordinates Wyckoff position Atom type
$\mathbf{B_{1}}$ = $- y_{1} \, \mathbf{a}_{1}+y_{1} \, \mathbf{a}_{2}+\frac{1}{4} \, \mathbf{a}_{3}$ = $b y_{1} \,\mathbf{\hat{y}}+\frac{1}{4}c \,\mathbf{\hat{z}}$ (4c) Cu I
$\mathbf{B_{2}}$ = $y_{1} \, \mathbf{a}_{1}- y_{1} \, \mathbf{a}_{2}+\frac{3}{4} \, \mathbf{a}_{3}$ = $- b y_{1} \,\mathbf{\hat{y}}+\frac{3}{4}c \,\mathbf{\hat{z}}$ (4c) Cu I
$\mathbf{B_{3}}$ = $- y_{2} \, \mathbf{a}_{1}+y_{2} \, \mathbf{a}_{2}+\frac{1}{4} \, \mathbf{a}_{3}$ = $b y_{2} \,\mathbf{\hat{y}}+\frac{1}{4}c \,\mathbf{\hat{z}}$ (4c) Mg I
$\mathbf{B_{4}}$ = $y_{2} \, \mathbf{a}_{1}- y_{2} \, \mathbf{a}_{2}+\frac{3}{4} \, \mathbf{a}_{3}$ = $- b y_{2} \,\mathbf{\hat{y}}+\frac{3}{4}c \,\mathbf{\hat{z}}$ (4c) Mg I
$\mathbf{B_{5}}$ = $- y_{3} \, \mathbf{a}_{1}+y_{3} \, \mathbf{a}_{2}+z_{3} \, \mathbf{a}_{3}$ = $b y_{3} \,\mathbf{\hat{y}}+c z_{3} \,\mathbf{\hat{z}}$ (8f) Al I
$\mathbf{B_{6}}$ = $y_{3} \, \mathbf{a}_{1}- y_{3} \, \mathbf{a}_{2}+\left(z_{3} + \frac{1}{2}\right) \, \mathbf{a}_{3}$ = $- b y_{3} \,\mathbf{\hat{y}}+c \left(z_{3} + \frac{1}{2}\right) \,\mathbf{\hat{z}}$ (8f) Al I
$\mathbf{B_{7}}$ = $- y_{3} \, \mathbf{a}_{1}+y_{3} \, \mathbf{a}_{2}- \left(z_{3} - \frac{1}{2}\right) \, \mathbf{a}_{3}$ = $b y_{3} \,\mathbf{\hat{y}}- c \left(z_{3} - \frac{1}{2}\right) \,\mathbf{\hat{z}}$ (8f) Al I
$\mathbf{B_{8}}$ = $y_{3} \, \mathbf{a}_{1}- y_{3} \, \mathbf{a}_{2}- z_{3} \, \mathbf{a}_{3}$ = $- b y_{3} \,\mathbf{\hat{y}}- c z_{3} \,\mathbf{\hat{z}}$ (8f) Al I

References

  • B. Heying, R.-D. Hoffmann, and R. Pöttgen, Structure Refinement of the S-Phase Precipitate MgCuAl$_{2}$, Z. Naturforsc. B 60, 491–494 (2005).

Prototype Generator

aflow --proto=A2BC_oC16_63_f_c_c --params=$a,b/a,c/a,y_{1},y_{2},y_{3},z_{3}$

Species:

Running:

Output: