Encyclopedia of Crystallographic Prototypes

AFLOW Prototype: A_aP4_2_aci-001

This structure originally had the label A_aP4_2_aci. Calls to that address will be redirected here.

If you are using this page, please cite:
M. J. Mehl, D. Hicks, C. Toher, O. Levy, R. M. Hanson, G. L. W. Hart, and S. Curtarolo, The AFLOW Library of Crystallographic Prototypes: Part 1, Comp. Mat. Sci. 136, S1-S828 (2017). (doi=10.1016/j.commatsci.2017.01.017)

Links to this page

https://aflow.org/p/G18C
or https://aflow.org/p/A_aP4_2_aci-001
or PDF Version

Cf Structure: A_aP4_2_aci-001

Picture of Structure; Click for Big Picture
Prototype Cf
AFLOW prototype label A_aP4_2_aci-001
ICSD 52913
Pearson symbol aP4
Space group number 2
Space group symbol $P\overline{1}$
AFLOW prototype command aflow --proto=A_aP4_2_aci-001
--params=$a, \allowbreak b/a, \allowbreak c/a, \allowbreak \alpha, \allowbreak \beta, \allowbreak \gamma, \allowbreak x_{3}, \allowbreak y_{3}, \allowbreak z_{3}$

  • This is a high-pressure phase, observed between 30 and 40 GPa.
  • The pressure at which the X-ray data was taken was not specified by (Roof, 1986).

\[ \begin{array}{ccc} \mathbf{a_{1}}&=&a \,\mathbf{\hat{x}}\\\mathbf{a_{2}}&=&b \cos{\gamma} \,\mathbf{\hat{x}}+b \sin{\gamma} \,\mathbf{\hat{y}}\\\mathbf{a_{3}}&=&c_{x} \,\mathbf{\hat{x}}+c_{y} \,\mathbf{\hat{y}}+c_{z} \,\mathbf{\hat{z}}\\c_{x} & = & c \cos{\beta} \\ c_{y} & = & c (\cos{\alpha} - \cos{\beta}\cos{\gamma}) / {\sin{\gamma}} \\ c_{z} & = & \sqrt{c^2 - c_{x}^2- c_{y}^2} \end{array}\]

Basis vectors

Lattice coordinates Cartesian coordinates Wyckoff position Atom type
$\mathbf{B_{1}}$ = $0$ = $0$ (1a) Cf I
$\mathbf{B_{2}}$ = $\frac{1}{2} \, \mathbf{a}_{2}$ = $\frac{1}{2}b \cos{\gamma} \,\mathbf{\hat{x}}+\frac{1}{2}b \sin{\gamma} \,\mathbf{\hat{y}}$ (1c) Cf II
$\mathbf{B_{3}}$ = $x_{3} \, \mathbf{a}_{1}+y_{3} \, \mathbf{a}_{2}+z_{3} \, \mathbf{a}_{3}$ = $\left(a x_{3} + b y_{3} \cos{\gamma} + c_{x} z_{3}\right) \,\mathbf{\hat{x}}+\left(b y_{3} \sin{\gamma} + c_{y} z_{3}\right) \,\mathbf{\hat{y}}+c_{z} z_{3} \,\mathbf{\hat{z}}$ (2i) Cf III
$\mathbf{B_{4}}$ = $- x_{3} \, \mathbf{a}_{1}- y_{3} \, \mathbf{a}_{2}- z_{3} \, \mathbf{a}_{3}$ = $- \left(a x_{3} + b y_{3} \cos{\gamma} + c_{x} z_{3}\right) \,\mathbf{\hat{x}}- \left(b y_{3} \sin{\gamma} + c_{y} z_{3}\right) \,\mathbf{\hat{y}}- c_{z} z_{3} \,\mathbf{\hat{z}}$ (2i) Cf III

References

  • R. B. Roof, Concerning the Structure of a High Pressure Phase in Californium Metal, J. Less-Common Met. 120, 345–349 (1986), doi:10.1016/0022-5088(86)90660-0.

Found in

  • P. Villars and L. Calvert, Pearson's Handbook of Crystallographic Data for Intermetallic Phases, vol. 2 (ASM International, Materials Park, OH, 1991), 2nd edn.

Prototype Generator

aflow --proto=A_aP4_2_aci --params=$a,b/a,c/a,\alpha,\beta,\gamma,x_{3},y_{3},z_{3}$

Species:

Running:

Output: