Encyclopedia of Crystallographic Prototypes

AFLOW Prototype: A4B_tI20_141_h_a-001

If you are using this page, please cite:
H. Eckert, S. Divilov, M. J. Mehl, D. Hicks, A. C. Zettel, M. Esters. X. Campilongo and S. Curtarolo, The AFLOW Library of Crystallographic Prototypes: Part 4. Submitted to Computational Materials Science.

Links to this page

https://aflow.org/p/NG21
or https://aflow.org/p/A4B_tI20_141_h_a-001
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β-ThCl$_{4}$ Structure: A4B_tI20_141_h_a-001

Picture of Structure; Click for Big Picture
Prototype Cl$_{4}$Th
AFLOW prototype label A4B_tI20_141_h_a-001
ICSD 26197
Pearson symbol tI20
Space group number 141
Space group symbol $I4_1/amd$
AFLOW prototype command aflow --proto=A4B_tI20_141_h_a-001
--params=$a, \allowbreak c/a, \allowbreak y_{2}, \allowbreak z_{2}$

  • $\beta$–ThCl$_{4}$ is stable above 405$^\circ$C. Below that temperature it transforms into $\alpha$–ThCl$_{4}$. (Mason, 1974)

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

Basis vectors

Lattice coordinates Cartesian coordinates Wyckoff position Atom type
$\mathbf{B_{1}}$ = $\frac{7}{8} \, \mathbf{a}_{1}+\frac{1}{8} \, \mathbf{a}_{2}+\frac{3}{4} \, \mathbf{a}_{3}$ = $\frac{3}{4}a \,\mathbf{\hat{y}}+\frac{1}{8}c \,\mathbf{\hat{z}}$ (4a) Th I
$\mathbf{B_{2}}$ = $\frac{1}{8} \, \mathbf{a}_{1}+\frac{7}{8} \, \mathbf{a}_{2}+\frac{1}{4} \, \mathbf{a}_{3}$ = $\frac{1}{2}a \,\mathbf{\hat{x}}- \frac{1}{4}a \,\mathbf{\hat{y}}+\frac{3}{8}c \,\mathbf{\hat{z}}$ (4a) Th I
$\mathbf{B_{3}}$ = $\left(y_{2} + z_{2}\right) \, \mathbf{a}_{1}+z_{2} \, \mathbf{a}_{2}+y_{2} \, \mathbf{a}_{3}$ = $a y_{2} \,\mathbf{\hat{y}}+c z_{2} \,\mathbf{\hat{z}}$ (16h) Cl I
$\mathbf{B_{4}}$ = $\left(- y_{2} + z_{2} + \frac{1}{2}\right) \, \mathbf{a}_{1}+z_{2} \, \mathbf{a}_{2}- \left(y_{2} - \frac{1}{2}\right) \, \mathbf{a}_{3}$ = $- a \left(y_{2} - \frac{1}{2}\right) \,\mathbf{\hat{y}}+c z_{2} \,\mathbf{\hat{z}}$ (16h) Cl I
$\mathbf{B_{5}}$ = $z_{2} \, \mathbf{a}_{1}+\left(- y_{2} + z_{2} + \frac{1}{2}\right) \, \mathbf{a}_{2}- y_{2} \, \mathbf{a}_{3}$ = $- a \left(y_{2} - \frac{1}{4}\right) \,\mathbf{\hat{x}}- \frac{1}{4}a \,\mathbf{\hat{y}}+c \left(z_{2} + \frac{1}{4}\right) \,\mathbf{\hat{z}}$ (16h) Cl I
$\mathbf{B_{6}}$ = $z_{2} \, \mathbf{a}_{1}+\left(y_{2} + z_{2}\right) \, \mathbf{a}_{2}+\left(y_{2} + \frac{1}{2}\right) \, \mathbf{a}_{3}$ = $a \left(y_{2} + \frac{1}{4}\right) \,\mathbf{\hat{x}}+\frac{1}{4}a \,\mathbf{\hat{y}}+c \left(z_{2} - \frac{1}{4}\right) \,\mathbf{\hat{z}}$ (16h) Cl I
$\mathbf{B_{7}}$ = $\left(y_{2} - z_{2} + \frac{1}{2}\right) \, \mathbf{a}_{1}- z_{2} \, \mathbf{a}_{2}+\left(y_{2} + \frac{1}{2}\right) \, \mathbf{a}_{3}$ = $a \left(y_{2} + \frac{1}{2}\right) \,\mathbf{\hat{y}}- c z_{2} \,\mathbf{\hat{z}}$ (16h) Cl I
$\mathbf{B_{8}}$ = $- \left(y_{2} + z_{2}\right) \, \mathbf{a}_{1}- z_{2} \, \mathbf{a}_{2}- y_{2} \, \mathbf{a}_{3}$ = $- a y_{2} \,\mathbf{\hat{y}}- c z_{2} \,\mathbf{\hat{z}}$ (16h) Cl I
$\mathbf{B_{9}}$ = $- z_{2} \, \mathbf{a}_{1}+\left(y_{2} - z_{2} + \frac{1}{2}\right) \, \mathbf{a}_{2}+y_{2} \, \mathbf{a}_{3}$ = $a \left(y_{2} + \frac{1}{4}\right) \,\mathbf{\hat{x}}- \frac{1}{4}a \,\mathbf{\hat{y}}- c \left(z_{2} - \frac{1}{4}\right) \,\mathbf{\hat{z}}$ (16h) Cl I
$\mathbf{B_{10}}$ = $- z_{2} \, \mathbf{a}_{1}- \left(y_{2} + z_{2}\right) \, \mathbf{a}_{2}- \left(y_{2} - \frac{1}{2}\right) \, \mathbf{a}_{3}$ = $- a \left(y_{2} - \frac{1}{4}\right) \,\mathbf{\hat{x}}+\frac{1}{4}a \,\mathbf{\hat{y}}- c \left(z_{2} + \frac{1}{4}\right) \,\mathbf{\hat{z}}$ (16h) Cl I

References

  • K. Mucker, G. S. Smith, Q. Johnson, and R. E. Elson, Refinement of the Crystal Structure of ThCl$_{4}$, Acta Crystallogr. Sect. B 25, 2362–2365 (1969), doi:10.1107/S056774086900570X.

Found in

  • J. T. Mason, M. C. Jha, and P. Chiotti, Crystal Structures of the ThCl$_{4}$ Polymorphs, J. Less-Common Met. 34, 143–151 (1974), doi:10.1016/0022-5088(74)90224-0.

Prototype Generator

aflow --proto=A4B_tI20_141_h_a --params=$a,c/a,y_{2},z_{2}$

Species:

Running:

Output: