Diamond (A4) Structure: A_cF8_227_a
| Prototype | : | C |
| AFLOW prototype label | : | A_cF8_227_a |
| Strukturbericht designation | : | $A4$ |
| Pearson symbol | : | cF8 |
| Space group number | : | 227 |
| Space group symbol | : | $\mbox{Fd}\bar{3}\mbox{m}$ |
| AFLOW prototype command | : | aflow --proto=A_cF8_227_a --params=$a$ |
Other elements with this structure
- Si, Ge, Sn
- This is the first crystal structure to be determined by X-ray diffraction.
Face-centered Cubic primitive vectors:
\[
\begin{array}{ccc}
\mathbf{a}_1 & = & \frac12 \, a \, \mathbf{\hat{y}} + \frac12 \, a \, \mathbf{\hat{z}} \\
\mathbf{a}_2 & = & \frac12 \, a \, \mathbf{\hat{x}} + \frac12 \, a \, \mathbf{\hat{z}} \\
\mathbf{a}_3 & = & \frac12 \, a \, \mathbf{\hat{x}} + \frac12 \, a \, \mathbf{\hat{y}} \\
\end{array}
\]
Basis vectors:
\[ \begin{array}{ccccccc} & & \mbox{Lattice Coordinates} & & \mbox{Cartesian Coordinates} &\mbox{Wyckoff Position} & \mbox{Atom Type} \\ \mathbf{B}_{1} & = &\frac18 \, \mathbf{a}_{1}+ \frac18 \, \mathbf{a}_{2}+ \frac18 \, \mathbf{a}_{3}& = &\frac18 \, a \, \mathbf{\hat{x}}+ \frac18 \, a \, \mathbf{\hat{y}}+ \frac18 \, a \, \mathbf{\hat{z}}& \left(8a\right) & \mbox{C} \\ \mathbf{B}_{2} & = &\frac78 \, \mathbf{a}_{1}+ \frac78 \, \mathbf{a}_{2}+ \frac78 \, \mathbf{a}_{3}& = &\frac78 \, a \, \mathbf{\hat{x}}+ \frac78 \, a \, \mathbf{\hat{y}}+ \frac78 \, a \, \mathbf{\hat{z}}& \left(8a\right) & \mbox{C} \\ \end{array} \]References
- W. H. Bragg and W. L. Bragg, The Structure of Diamond, Proc. R. Soc. A Math. Phys. Eng. Sci. 89, 277–291 (1913), doi:10.1098/rspa.1913.0084.