Pt8Ti Structure: A8B_tI18_139_hi_a

Picture of Structure; Click for Big Picture
Prototype : Pt8Ti
AFLOW prototype label : A8B_tI18_139_hi_a
Strukturbericht designation : None
Pearson symbol : tI18
Space group number : 139
Space group symbol : $\mbox{I4/mmm}$
AFLOW prototype command : aflow --proto=A8B_tI18_139_hi_a
--params=
$a$,$c/a$,$x_{2}$,$x_{3}$


Other compounds with this structure

  • NbNi8

  • $a = 3/\left(\sqrt{2}\right)a_{fcc}$, $c = a_{fcc}$, $x_2 = 1/3$, and $x_3 = 1/3$, the atoms are on the sites of the fcc lattice. The pictures here are drawn with these parameters, with $a_{fcc}$ appropriate for nickel. Compare this to the very similar V4Zn5 structure.

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:

\[ \begin{array}{ccccccc} & & \mbox{Lattice Coordinates} & & \mbox{Cartesian Coordinates} &\mbox{Wyckoff Position} & \mbox{Atom Type} \\ \mathbf{B}_{1} & =&0 \, \mathbf{a}_{1} + 0 \, \mathbf{a}_{2} + 0 \, \mathbf{a}_{3} & =&0 \mathbf{\hat{x}} + 0 \mathbf{\hat{y}} + 0 \mathbf{\hat{z}} & \left(2a\right) & \mbox{Ti} \\ \mathbf{B}_{2} & =&x_{2} \, \mathbf{a}_{1}+ x_{2} \, \mathbf{a}_{2}+ 2x_{2} \, \mathbf{a}_{3}& =&x_{2} \, a \, \mathbf{\hat{x}}+ x_{2} \, a \, \mathbf{\hat{y}}& \left(8h\right) & \mbox{Pt I} \\ \mathbf{B}_{3} & =&- x_{2} \, \mathbf{a}_{1}- x_{2} \, \mathbf{a}_{2}- 2x_{2} \, \mathbf{a}_{3}& =&- x_{2} \, a \, \mathbf{\hat{x}}- x_{2} \, a \, \mathbf{\hat{y}}& \left(8h\right) & \mbox{Pt I} \\ \mathbf{B}_{4} & =&x_{2} \, \mathbf{a}_{1}- x_{2} \, \mathbf{a}_{2}& =&- x_{2} \, a \, \mathbf{\hat{x}}+ x_{2} \, a \, \mathbf{\hat{y}}& \left(8h\right) & \mbox{Pt I} \\ \mathbf{B}_{5} & =&- x_{2} \, \mathbf{a}_{1}+ x_{2} \, \mathbf{a}_{2}& =&x_{2} \, a \, \mathbf{\hat{x}}- x_{2} \, a \, \mathbf{\hat{y}}& \left(8h\right) & \mbox{Pt I} \\ \mathbf{B}_{6} & =&x_{3} \, \mathbf{a}_{2}+ x_{3} \, \mathbf{a}_{3}& =&x_{3} \, a \, \mathbf{\hat{x}}& \left(8i\right) & \mbox{Pt II} \\ \mathbf{B}_{7} & =&- x_{3} \, \mathbf{a}_{2}- x_{3} \, \mathbf{a}_{3}& =&- x_{3} \, a \, \mathbf{\hat{x}}& \left(8i\right) & \mbox{Pt II} \\ \mathbf{B}_{8} & =&x_{3} \, \mathbf{a}_{1}+ x_{3} \, \mathbf{a}_{3}& =&x_{3} \, a \, \mathbf{\hat{y}}& \left(8i\right) & \mbox{Pt II} \\ \mathbf{B}_{9} & =&- x_{3} \, \mathbf{a}_{1}- x_{3} \, \mathbf{a}_{3}& =&- x_{3} \, a \, \mathbf{\hat{y}}& \left(8i\right) & \mbox{Pt II} \\ \end{array} \]

References

  • R. H. Taylor, S. Curtarolo, and G. L. W. Hart, Predictions of the Pt8Ti phase in unexpected systems, J. Am. Chem. Soc. 132, 6851–6854 (2010), doi:10.1021/ja101890k.

Found in

  • P. Villars and L. Calvert, Pearson's Handbook of Crystallographic Data for Intermetallic Phases (ASM International, Materials Park, OH, 1991), 2nd edn., pp. 5011.

Geometry files


Prototype Generator

aflow --proto=A8B_tI18_139_hi_a --params=

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