Encyclopedia of Crystallographic Prototypes

AFLOW Prototype: A2B_oC12_38_de_ab

  • 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)
  • D. Hicks, M. J. Mehl, E. Gossett, C. Toher, O. Levy, R. M. Hanson, G. L. W. Hart, and S. Curtarolo, The AFLOW Library of Crystallographic Prototypes: Part 2, Comp. Mat. Sci. 161, S1-S1011 (2019). (doi=10.1016/j.commatsci.2018.10.043)
  • 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)

Au2V Structure: A2B_oC12_38_de_ab

Picture of Structure; Click for Big Picture
Prototype : Au2V
AFLOW prototype label : A2B_oC12_38_de_ab
Strukturbericht designation : None
Pearson symbol : oC12
Space group number : 38
Space group symbol : $\text{Amm2}$
AFLOW prototype command : aflow --proto=A2B_oC12_38_de_ab
--params=
$a$,$b/a$,$c/a$,$z_{1}$,$z_{2}$,$y_{3}$,$z_{3}$,$y_{4}$,$z_{4}$


Other compounds with this structure

  • Cu2Ti, Pt2Ta

  • Note that the published atomic positions put the system in the Cmcm space group, despite the author's statement that the system is in the Amm2 space group. We forced this system into the Amm2 space group by slightly shifting the $y_{4}$ coordinate. If $y_{3} = y_{4}$ then the space group becomes Cmcm.

Base-centered Orthorhombic primitive vectors:

\[ \begin{array}{ccc} \mathbf{a}_1 & = & a \, \mathbf{\hat{x}} \\ \mathbf{a}_2 & = & \frac12 \, b \, \mathbf{\hat{y}} - \frac12 \, c \, \mathbf{\hat{z}} \\ \mathbf{a}_3 & = & \frac12 \, b \, \mathbf{\hat{y}} + \frac12 \, c \, \mathbf{\hat{z}} \end{array} \]

Basis vectors:

\[ \begin{array}{ccccccc} & & \text{Lattice Coordinates} & & \text{Cartesian Coordinates} &\text{Wyckoff Position} & \text{Atom Type} \\ \mathbf{B}_{1} & =& - z_{1} \, \mathbf{a}_{2} + z_{1} \, \mathbf{a}_{3}& =& z_{1} \, c \, \mathbf{\hat{z}}& \left(2a\right) & \text{V I} \\ \mathbf{B}_{2} & =& \frac12 \, \mathbf{a}_{1} - z_{2} \, \mathbf{a}_{2} + z_{2} \, \mathbf{a}_{3}& =& \frac12 \, a \, \mathbf{\hat{x}} + z_{2} \, c \, \mathbf{\hat{z}}& \left(2b\right) & \text{V II} \\ \mathbf{B}_{3} & =& \left(y_{3} - z_{3}\right) \, \mathbf{a}_{2} + \left(y_{3} + z_{3}\right) \, \mathbf{a}_{3}& =& y_{3} \, b \, \mathbf{\hat{y}} + z_{3} \, c \, \mathbf{\hat{z}}& \left(4d\right) & \text{Au I} \\ \mathbf{B}_{4} & =& - \left(y_{3} + z_{3}\right) \, \mathbf{a}_{2} + \left(z_{3} - y_{3}\right) \, \mathbf{a}_{3}& =& - y_{3} \, b \, \mathbf{\hat{y}} + z_{3} \, c \, \mathbf{\hat{z}}& \left(4d\right) & \text{Au I} \\ \mathbf{B}_{5} & =& \frac12 \, \mathbf{a}_{1} + \left(y_{4} - z_{4}\right) \, \mathbf{a}_{2} + \left(y_{4} + z_{4}\right) \, \mathbf{a}_{3}& =& \frac12 \, a \, \mathbf{\hat{x}} + y_{4} \, b \, \mathbf{\hat{y}} + z_{4} \, c \, \mathbf{\hat{z}}& \left(4e\right) & \text{Au II} \\ \mathbf{B}_{6} & =& \frac12 \, \mathbf{a}_{1} - \left(y_{4} + z_{4}\right) \, \mathbf{a}_{2} + \left(z_{4} - y_{4}\right) \, \mathbf{a}_{3}& =& \frac12 \, a \, \mathbf{\hat{x}} - y_{4} \, b \, \mathbf{\hat{y}} + z_{4} \, c \, \mathbf{\hat{z}}& \left(4e\right) & \text{Au II} \\ \end{array} \]

References

  • E. Stolz and K. Schubert, Strukturuntersuchungen in einigen zu T–B homologen und quasihomologen Systemen, Z. Metallkd. 53, 433–444 (1962).

Found in

  • P. Villars, Material Phases Data System ((MPDS), CH–6354 Vitznau, Switzerland, 2014). Accessed through the Springer Materials site.

Geometry files


Prototype Generator

aflow --proto=A2B_oC12_38_de_ab --params=

Species:

Running:

Output: