Sc–V (High–pressure) Structure: A_hP6_178_a

Picture of Structure; Click for Big Picture
Prototype : Sc
AFLOW prototype label : A_hP6_178_a
Strukturbericht designation : None
Pearson symbol : hP6
Space group number : 178
Space group symbol : $P6_{1}22$
AFLOW prototype command : aflow --proto=A_hP6_178_a
--params=
$a$,$c/a$,$x_{1}$


  • This high pressure phase of scandium becomes stable at 240 GPa. We use the experimental data at 242 GPa and 297 K. This chiral structure could also have been presented in the enantiomorphic space group $P6_{5}22$ (#179).

Hexagonal primitive vectors:

\[ \begin{array}{ccc} \mathbf{a}_1 & = & \frac12 \, a \, \mathbf{\hat{x}} - \frac{\sqrt3}2 \, a \, \mathbf{\hat{y}} \\ \mathbf{a}_2 & = & \frac12 \, a \, \mathbf{\hat{x}} + \frac{\sqrt3}2 \, a \, \mathbf{\hat{y}} \\ \mathbf{a}_3 & = & c \, \mathbf{\hat{z}} \\ \end{array} \]

Basis vectors:

\[ \begin{array}{ccccccc} & & \mbox{Lattice Coordinates} & & \mbox{Cartesian Coordinates} &\mbox{Wyckoff Position} & \mbox{Atom Type} \\ \mathbf{B}_{1} & = & x_{1} \, \mathbf{a}_{1} & = & \frac{1}{2}x_{1}a \, \mathbf{\hat{x}}-\frac{\sqrt{3}}{2}x_{1}a \, \mathbf{\hat{y}} & \left(6a\right) & \mbox{Sc} \\ \mathbf{B}_{2} & = & x_{1} \, \mathbf{a}_{2} + \frac{1}{3} \, \mathbf{a}_{3} & = & \frac{1}{2}x_{1}a \, \mathbf{\hat{x}} + \frac{\sqrt{3}}{2}x_{1}a \, \mathbf{\hat{y}} + \frac{1}{3}c \, \mathbf{\hat{z}} & \left(6a\right) & \mbox{Sc} \\ \mathbf{B}_{3} & = & -x_{1} \, \mathbf{a}_{1}-x_{1} \, \mathbf{a}_{2} + \frac{2}{3} \, \mathbf{a}_{3} & = & -x_{1}a \, \mathbf{\hat{x}} + \frac{2}{3}c \, \mathbf{\hat{z}} & \left(6a\right) & \mbox{Sc} \\ \mathbf{B}_{4} & = & -x_{1} \, \mathbf{a}_{1} + \frac{1}{2} \, \mathbf{a}_{3} & = & -\frac{1}{2}x_{1}a \, \mathbf{\hat{x}} + \frac{\sqrt{3}}{2}x_{1}a \, \mathbf{\hat{y}} + \frac{1}{2}c \, \mathbf{\hat{z}} & \left(6a\right) & \mbox{Sc} \\ \mathbf{B}_{5} & = & -x_{1} \, \mathbf{a}_{2} + \frac{5}{6} \, \mathbf{a}_{3} & = & -\frac{1}{2}x_{1}a \, \mathbf{\hat{x}}-\frac{\sqrt{3}}{2}x_{1}a \, \mathbf{\hat{y}} + \frac{5}{6}c \, \mathbf{\hat{z}} & \left(6a\right) & \mbox{Sc} \\ \mathbf{B}_{6} & = & x_{1} \, \mathbf{a}_{1} + x_{1} \, \mathbf{a}_{2} + \frac{1}{6} \, \mathbf{a}_{3} & = & x_{1}a \, \mathbf{\hat{x}} + \frac{1}{6}c \, \mathbf{\hat{z}} & \left(6a\right) & \mbox{Sc} \\ \end{array} \]

References

  • Y. Akahama, H. Fujihisa, and H. Kawamura, New Helical Chain Structure for Scandium at 240 GPa, Phys. Rev. Lett. 94, 195503 (2005), doi:10.1103/PhysRevLett.94.195503.

Geometry files


Prototype Generator

aflow --proto=A_hP6_178_a --params=

Species:

Running:

Output: