Encyclopedia of Crystallographic Prototypes

AFLOW Prototype: A6B2C_hP9_150_ef_d_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.

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https://aflow.org/p/R3Z7
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β-Na$_{2}$ThF$_{6}$ Structure: A6B2C_hP9_150_ef_d_a-001

Picture of Structure; Click for Big Picture
Prototype F$_{6}$Na$_{2}$Th
AFLOW prototype label A6B2C_hP9_150_ef_d_a-001
ICSD 418148
Pearson symbol hP9
Space group number 150
Space group symbol $P321$
AFLOW prototype command aflow --proto=A6B2C_hP9_150_ef_d_a-001
--params=$a, \allowbreak c/a, \allowbreak z_{2}, \allowbreak x_{3}, \allowbreak x_{4}$

Other compounds with this structure

$\beta_{2}$-K$_{2}$UF$_{6}$


  • When $z_{2} = 1/2$ this transforms into $\delta$–Na$_{2}$ThF$_{6}$ which has the hexagonal $\beta_{1}$-K$_{2}$UF$_{6}$ structure.
  • We use the data from (Grzechnik, 2007) taken at 100K and ambient pressure.

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

Basis vectors

Lattice coordinates Cartesian coordinates Wyckoff position Atom type
$\mathbf{B_{1}}$ = $0$ = $0$ (1a) Th I
$\mathbf{B_{2}}$ = $\frac{1}{3} \, \mathbf{a}_{1}+\frac{2}{3} \, \mathbf{a}_{2}+z_{2} \, \mathbf{a}_{3}$ = $\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{\sqrt{3}}{6}a \,\mathbf{\hat{y}}+c z_{2} \,\mathbf{\hat{z}}$ (2d) Na I
$\mathbf{B_{3}}$ = $\frac{2}{3} \, \mathbf{a}_{1}+\frac{1}{3} \, \mathbf{a}_{2}- z_{2} \, \mathbf{a}_{3}$ = $\frac{1}{2}a \,\mathbf{\hat{x}}- \frac{\sqrt{3}}{6}a \,\mathbf{\hat{y}}- c z_{2} \,\mathbf{\hat{z}}$ (2d) Na I
$\mathbf{B_{4}}$ = $x_{3} \, \mathbf{a}_{1}$ = $\frac{1}{2}a x_{3} \,\mathbf{\hat{x}}- \frac{\sqrt{3}}{2}a x_{3} \,\mathbf{\hat{y}}$ (3e) F I
$\mathbf{B_{5}}$ = $x_{3} \, \mathbf{a}_{2}$ = $\frac{1}{2}a x_{3} \,\mathbf{\hat{x}}+\frac{\sqrt{3}}{2}a x_{3} \,\mathbf{\hat{y}}$ (3e) F I
$\mathbf{B_{6}}$ = $- x_{3} \, \mathbf{a}_{1}- x_{3} \, \mathbf{a}_{2}$ = $- a x_{3} \,\mathbf{\hat{x}}$ (3e) F I
$\mathbf{B_{7}}$ = $x_{4} \, \mathbf{a}_{1}+\frac{1}{2} \, \mathbf{a}_{3}$ = $\frac{1}{2}a x_{4} \,\mathbf{\hat{x}}- \frac{\sqrt{3}}{2}a x_{4} \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}$ (3f) F II
$\mathbf{B_{8}}$ = $x_{4} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ = $\frac{1}{2}a x_{4} \,\mathbf{\hat{x}}+\frac{\sqrt{3}}{2}a x_{4} \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}$ (3f) F II
$\mathbf{B_{9}}$ = $- x_{4} \, \mathbf{a}_{1}- x_{4} \, \mathbf{a}_{2}+\frac{1}{2} \, \mathbf{a}_{3}$ = $- a x_{4} \,\mathbf{\hat{x}}+\frac{1}{2}c \,\mathbf{\hat{z}}$ (3f) F II

References

  • A. Grzechnik, M. Fechtelkord, W. Morgenroth, J. M. Posse, and K. Friese, Crystal structure and stability of β-Na$_{2}$ThF$_{6}$ at non-ambient conditions, J. Phys.: Condens. Matter 19, 266219 (2007), doi:10.1088/0953-8984/19/26/266219.

Found in

  • A. Grzechnik, C. C. Underwood, J. W. Kolis, and K. Friese, Crystal structures and stability of K$_{2}$ThF$_{6}$ and K$_{7}$Th$_{6}$F$_{31}$ on compression, J. Fluor. Chem. 150, 8–13 (2013), doi:10.1016/j.jfluchem.2013.02.024.

Prototype Generator

aflow --proto=A6B2C_hP9_150_ef_d_a --params=$a,c/a,z_{2},x_{3},x_{4}$

Species:

Running:

Output: