Encyclopedia of Crystallographic Prototypes

AFLOW Prototype: A2B_oC12_38_de_ab-001

This structure originally had the label A2B_oC12_38_de_ab. Calls to that address will be redirected here.

If you are using this page, please cite:
M. J. Mehl, D. Hicks, C. Toher, O. Levy, R. M. Hanson, G. L. W. Hart, and S. Curtarolo, The AFLOW Library of Crystallographic Prototypes: Part 1, Comp. Mat. Sci. 136, S1-S828 (2017). (doi=10.1016/j.commatsci.2017.01.017)

Links to this page

https://aflow.org/p/PCHF
or https://aflow.org/p/A2B_oC12_38_de_ab-001
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Au$_{2}$V Structure: A2B_oC12_38_de_ab-001

Picture of Structure; Click for Big Picture
Prototype Au$_{2}$V
AFLOW prototype label A2B_oC12_38_de_ab-001
ICSD 58614
Pearson symbol oC12
Space group number 38
Space group symbol $Amm2$
AFLOW prototype command aflow --proto=A2B_oC12_38_de_ab-001
--params=$a, \allowbreak b/a, \allowbreak c/a, \allowbreak z_{1}, \allowbreak z_{2}, \allowbreak y_{3}, \allowbreak z_{3}, \allowbreak y_{4}, \allowbreak z_{4}$

Other compounds with this structure

Cu$_{2}$Ti,  Pt$_{2}$Ta


  • The published atomic positions put the system in the $Cmcm$ #65 space group, despite the authors' statement that the system is in the $Amm2$ #38. We forced this system into $Amm2$ by slightly shifting the $y_{4}$ cordinate. If $y_{3} = y_{4}$ then the space group becomes $Cmcm$.
  • Space group $Amm2$ #38 allows an arbitrary choice of the origin of the $z$-axis. Here we follow (Stolz, 1962) and set $z_{2} = 0$ for the Au-II position.

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

Basis vectors

Lattice coordinates Cartesian coordinates Wyckoff position Atom type
$\mathbf{B_{1}}$ = $- z_{1} \, \mathbf{a}_{2}+z_{1} \, \mathbf{a}_{3}$ = $c z_{1} \,\mathbf{\hat{z}}$ (2a) V I
$\mathbf{B_{2}}$ = $\frac{1}{2} \, \mathbf{a}_{1}- z_{2} \, \mathbf{a}_{2}+z_{2} \, \mathbf{a}_{3}$ = $\frac{1}{2}a \,\mathbf{\hat{x}}+c z_{2} \,\mathbf{\hat{z}}$ (2b) V II
$\mathbf{B_{3}}$ = $\left(y_{3} - z_{3}\right) \, \mathbf{a}_{2}+\left(y_{3} + z_{3}\right) \, \mathbf{a}_{3}$ = $b y_{3} \,\mathbf{\hat{y}}+c z_{3} \,\mathbf{\hat{z}}$ (4d) Au I
$\mathbf{B_{4}}$ = $- \left(y_{3} + z_{3}\right) \, \mathbf{a}_{2}- \left(y_{3} - z_{3}\right) \, \mathbf{a}_{3}$ = $- b y_{3} \,\mathbf{\hat{y}}+c z_{3} \,\mathbf{\hat{z}}$ (4d) Au I
$\mathbf{B_{5}}$ = $\frac{1}{2} \, \mathbf{a}_{1}+\left(y_{4} - z_{4}\right) \, \mathbf{a}_{2}+\left(y_{4} + z_{4}\right) \, \mathbf{a}_{3}$ = $\frac{1}{2}a \,\mathbf{\hat{x}}+b y_{4} \,\mathbf{\hat{y}}+c z_{4} \,\mathbf{\hat{z}}$ (4e) Au II
$\mathbf{B_{6}}$ = $\frac{1}{2} \, \mathbf{a}_{1}- \left(y_{4} + z_{4}\right) \, \mathbf{a}_{2}- \left(y_{4} - z_{4}\right) \, \mathbf{a}_{3}$ = $\frac{1}{2}a \,\mathbf{\hat{x}}- b y_{4} \,\mathbf{\hat{y}}+c z_{4} \,\mathbf{\hat{z}}$ (4e) Au II

References

  • E. Stolz and K. Schubert, Strukturuntersuchungen in einigen zu T$^4$-B$^1$ homologen und quasihomologen Systemen, Z. Metallkd. 53, 433–444 (1962), doi:10.1515/ijmr-1962-530701.

Found in

  • P. Villars, Au2V Crystal Structure (2016). PAULING FILE in: Inorganic Solid Phases, SpringerMaterials (online database), Springer, Heidelberg (ed.) SpringerMaterials.

Prototype Generator

aflow --proto=A2B_oC12_38_de_ab --params=$a,b/a,c/a,z_{1},z_{2},y_{3},z_{3},y_{4},z_{4}$

Species:

Running:

Output: