MoSi2 ($C11_{b}$) Structure: AB2_tI6_139_a_e

Picture of Structure; Click for Big Picture
Prototype : MoSi2
AFLOW prototype label : AB2_tI6_139_a_e
Strukturbericht designation : $C11_{b}$
Pearson symbol : tI6
Space group number : 139
Space group symbol : $\mbox{I4/mmm}$
AFLOW prototype command : aflow --proto=AB2_tI6_139_a_e
--params=
$a$,$c/a$,$z_{2}$


Other compounds with this structure

  • CaC2, CdTi2

  • When $c=3a$ and $z_{2}=1/3$ the atoms are on the sites of a body-centered cubic lattice. For MoSi2 itself, (Harada, 1998) gives $c/a = 2.45$ and $z_{2}=0.3353$. Other compounds in this structure have very different values of $c/a$ and even $z_{2}$.

Body-centered Tetragonal primitive vectors:

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

Basis vectors:

\[ \begin{array}{ccccccc} & & \mbox{Lattice Coordinates} & & \mbox{Cartesian Coordinates} &\mbox{Wyckoff Position} & \mbox{Atom Type} \\ \mathbf{B}_{1} & = & 0 \, \mathbf{a}_{1} + 0 \, \mathbf{a}_{2} + 0 \, \mathbf{a}_{3} & = & 0 \mathbf{\hat{x}} + 0 \mathbf{\hat{y}} + 0 \mathbf{\hat{z}} & \left(2a\right) & \mbox{Mo} \\ \mathbf{B}_{2} & =& z_{2} \, \mathbf{a}_{1} + z_{2} \, \mathbf{a}_{2}& =& z_{2} \, c \, \mathbf{\hat{z}}& \left(4e\right) & \mbox{Si} \\ \mathbf{B}_{3} & =& - z_{2} \, \mathbf{a}_{1} - z_{2} \, \mathbf{a}_{2}& =& - z_{2} \, c \, \mathbf{\hat{z}}& \left(4e\right) & \mbox{Si} \\ \end{array} \]

References

  • Y. Harada, M. Morinaga, D. Saso, M. Takata, and M. Sakata, Refinement of crystal structure in MoSi2, Intermetallics 6, 523–527 (1998), doi:10.1016/S0966-9795(97)00102-7.

Geometry files


Prototype Generator

aflow --proto=AB2_tI6_139_a_e --params=

Species:

Running:

Output: