Encyclopedia of Crystallographic Prototypes

AFLOW Prototype: A4B_oI20_74_aeh_e-001

This structure originally had the label A4B_oI20_74_beh_e. Calls to that address will be redirected here.

If you are using this page, please cite:
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)

Links to this page

https://aflow.org/p/FNF2
or https://aflow.org/p/A4B_oI20_74_aeh_e-001
or PDF Version

Al$_{4}$U ($D1_{b}$) Structure: A4B_oI20_74_aeh_e-001

Picture of Structure; Click for Big Picture
Prototype Al$_{4}$U
AFLOW prototype label A4B_oI20_74_aeh_e-001
Strukturbericht designation $D1_{b}$
ICSD 240127
Pearson symbol oI20
Space group number 74
Space group symbol $Imma$
AFLOW prototype command aflow --proto=A4B_oI20_74_aeh_e-001
--params=$a, \allowbreak b/a, \allowbreak c/a, \allowbreak z_{2}, \allowbreak z_{3}, \allowbreak y_{4}, \allowbreak z_{4}$

Other compounds with this structure

Al$_{4}$Gd,  Al$_{4}$Np,  Al$_{4}$Pu,  Ga$_{4}$Pu


  • We replaced the rather obscure (Borgstedt, 1989) reference by the modern work of (Tougait, 2004).

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

Basis vectors

Lattice coordinates Cartesian coordinates Wyckoff position Atom type
$\mathbf{B_{1}}$ = $0$ = $0$ (4a) Al I
$\mathbf{B_{2}}$ = $\frac{1}{2} \, \mathbf{a}_{1}+\frac{1}{2} \, \mathbf{a}_{3}$ = $\frac{1}{2}b \,\mathbf{\hat{y}}$ (4a) Al I
$\mathbf{B_{3}}$ = $\left(z_{2} + \frac{1}{4}\right) \, \mathbf{a}_{1}+z_{2} \, \mathbf{a}_{2}+\frac{1}{4} \, \mathbf{a}_{3}$ = $\frac{1}{4}b \,\mathbf{\hat{y}}+c z_{2} \,\mathbf{\hat{z}}$ (4e) Al II
$\mathbf{B_{4}}$ = $- \left(z_{2} - \frac{3}{4}\right) \, \mathbf{a}_{1}- z_{2} \, \mathbf{a}_{2}+\frac{3}{4} \, \mathbf{a}_{3}$ = $\frac{3}{4}b \,\mathbf{\hat{y}}- c z_{2} \,\mathbf{\hat{z}}$ (4e) Al II
$\mathbf{B_{5}}$ = $\left(z_{3} + \frac{1}{4}\right) \, \mathbf{a}_{1}+z_{3} \, \mathbf{a}_{2}+\frac{1}{4} \, \mathbf{a}_{3}$ = $\frac{1}{4}b \,\mathbf{\hat{y}}+c z_{3} \,\mathbf{\hat{z}}$ (4e) U I
$\mathbf{B_{6}}$ = $- \left(z_{3} - \frac{3}{4}\right) \, \mathbf{a}_{1}- z_{3} \, \mathbf{a}_{2}+\frac{3}{4} \, \mathbf{a}_{3}$ = $\frac{3}{4}b \,\mathbf{\hat{y}}- c z_{3} \,\mathbf{\hat{z}}$ (4e) U I
$\mathbf{B_{7}}$ = $\left(y_{4} + z_{4}\right) \, \mathbf{a}_{1}+z_{4} \, \mathbf{a}_{2}+y_{4} \, \mathbf{a}_{3}$ = $b y_{4} \,\mathbf{\hat{y}}+c z_{4} \,\mathbf{\hat{z}}$ (8h) Al III
$\mathbf{B_{8}}$ = $\left(- y_{4} + z_{4} + \frac{1}{2}\right) \, \mathbf{a}_{1}+z_{4} \, \mathbf{a}_{2}- \left(y_{4} - \frac{1}{2}\right) \, \mathbf{a}_{3}$ = $- b \left(y_{4} - \frac{1}{2}\right) \,\mathbf{\hat{y}}+c z_{4} \,\mathbf{\hat{z}}$ (8h) Al III
$\mathbf{B_{9}}$ = $\left(y_{4} - z_{4} + \frac{1}{2}\right) \, \mathbf{a}_{1}- z_{4} \, \mathbf{a}_{2}+\left(y_{4} + \frac{1}{2}\right) \, \mathbf{a}_{3}$ = $b \left(y_{4} + \frac{1}{2}\right) \,\mathbf{\hat{y}}- c z_{4} \,\mathbf{\hat{z}}$ (8h) Al III
$\mathbf{B_{10}}$ = $- \left(y_{4} + z_{4}\right) \, \mathbf{a}_{1}- z_{4} \, \mathbf{a}_{2}- y_{4} \, \mathbf{a}_{3}$ = $- b y_{4} \,\mathbf{\hat{y}}- c z_{4} \,\mathbf{\hat{z}}$ (8h) Al III

References

  • O. Tougait and H. Noël, Stoichiometry of UAl$_{4}$, Intermetallics 12, 219–223 (2004), doi:10.1016/j.intermet.2003.09.012.
  • H. U. Borgstedt and H. Wedemeyer, Gmelin Handbook of Inorganic Chemistry (Springer-Verlag, Berlin Heidelberg, 1989), vol. Supplement B 2, chap. 3, p. 144.

Prototype Generator

aflow --proto=A4B_oI20_74_aeh_e --params=$a,b/a,c/a,z_{2},z_{3},y_{4},z_{4}$

Species:

Running:

Output: