Encyclopedia of Crystallographic Prototypes

AFLOW Prototype: AB_cI16_199_a_a

  • 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)

CoU ($B_{a}$) Structure: AB_cI16_199_a_a

Picture of Structure; Click for Big Picture
Prototype : CoU
AFLOW prototype label : AB_cI16_199_a_a
Strukturbericht designation : $B_{a}$
Pearson symbol : cI16
Space group number : 199
Space group symbol : $\text{I2}_{1}\text{3}$
AFLOW prototype command : aflow --proto=AB_cI16_199_a_a
--params=
$a$,$x_{1}$,$x_{2}$


Other compounds with this structure

  • Ga2Pu3

  • When $x_{1} = 1/4$ and $x_{2} = 0$, or visa versa, this structure reduces to CsCl (B2) with aB2 = 1/2 a$.

Body-centered Cubic primitive vectors:

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

Basis vectors:

\[ \begin{array}{ccccccc} & & \text{Lattice Coordinates} & & \text{Cartesian Coordinates} &\text{Wyckoff Position} & \text{Atom Type} \\ \mathbf{B}_{1} & = &2 x_{1} \, \mathbf{a}_{1}+ 2 x_{1} \, \mathbf{a}_{2}+ 2 x_{1} \, \mathbf{a}_{3}& = &x_{1} \, a \, \mathbf{\hat{x}}+ x_{1} \, a \, \mathbf{\hat{y}}+ x_{1} \, a \, \mathbf{\hat{z}}& \left(8a\right) & \text{Co} \\ \mathbf{B}_{2} & = &\frac12 \, \mathbf{a}_{1}+ \left(\frac12 - 2 x_{1}\right) \, \mathbf{a}_{3}& = &- x_{1} \, a \, \mathbf{\hat{x}}+ \left(\frac12 - x_{1}\right) \, a \, \mathbf{\hat{y}}+ x_{1} \, a \, \mathbf{\hat{z}}& \left(8a\right) & \text{Co} \\ \mathbf{B}_{3} & = &\left(\frac12 - 2 x_{1}\right) \, \mathbf{a}_{2}+ \frac12 \, \mathbf{a}_{3}& = &\left(\frac12 - x_{1}\right) \, a \, \mathbf{\hat{x}}+ x_{1} \, a \, \mathbf{\hat{y}}- x_{1} \, a \, \mathbf{\hat{z}}& \left(8a\right) & \text{Co} \\ \mathbf{B}_{4} & = &\left(\frac12 - 2 x_{1}\right) \, \mathbf{a}_{1}+ \frac12 \, \mathbf{a}_{2}& = &x_{1} \, a \, \mathbf{\hat{x}}- x_{1} \, a \, \mathbf{\hat{y}}+ \left(\frac12 - x_{1}\right) \, a \, \mathbf{\hat{z}}& \left(8a\right) & \text{Co} \\ \mathbf{B}_{5} & = &2 x_{2} \, \mathbf{a}_{1}+ 2 x_{2} \, \mathbf{a}_{2}+ 2 x_{2} \, \mathbf{a}_{3}& = &x_{2} \, a \, \mathbf{\hat{x}}+ x_{2} \, a \, \mathbf{\hat{y}}+ x_{2} \, a \, \mathbf{\hat{z}}& \left(8a\right) & \text{U} \\ \mathbf{B}_{6} & = &\frac12 \, \mathbf{a}_{1}+ \left(\frac12 - 2 x_{2}\right) \, \mathbf{a}_{3}& = &- x_{2} \, a \, \mathbf{\hat{x}}+ \left(\frac12 - x_{2}\right) \, a \, \mathbf{\hat{y}}+ x_{2} \, a \, \mathbf{\hat{z}}& \left(8a\right) & \text{U} \\ \mathbf{B}_{7} & = &\left(\frac12 - 2 x_{2}\right) \, \mathbf{a}_{2}+ \frac12 \, \mathbf{a}_{3}& = &\left(\frac12 - x_{2}\right) \, a \, \mathbf{\hat{x}}+ x_{2} \, a \, \mathbf{\hat{y}}- x_{2} \, a \, \mathbf{\hat{z}}& \left(8a\right) & \text{U} \\ \mathbf{B}_{8} & = &\left(\frac12 - 2 x_{2}\right) \, \mathbf{a}_{1}+ \frac12 \, \mathbf{a}_{2}& = &x_{2} \, a \, \mathbf{\hat{x}}- x_{2} \, a \, \mathbf{\hat{y}}+ \left(\frac12 - x_{2}\right) \, a \, \mathbf{\hat{z}}& \left(8a\right) & \text{U} \\ \end{array} \]

References

  • N. C. Baenziger, R. E. Rundle, A. I. Snow, and A. S. Wilson, Compounds of uranium with the transition metals of the first long period, Acta Cryst. 3, 34–40 (1950), doi:10.1107/S0365110X50000082.

Found in

  • F. A. Rough and A. A. Bauer, Constitution of Uranium and Thorium Alloys, Report No. BMI–1300 (UC–25 Metallurgy and Ceramics, TID–4500, 1958), 13th edn.

Geometry files


Prototype Generator

aflow --proto=AB_cI16_199_a_a --params=

Species:

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