$I1_{3}$ (SrCl2·(H2O)6) (obsolete) Structure : A2B6C_hP9_162_d_k_a
| Prototype | : | Cl2(H2O)6Sr |
| AFLOW prototype label | : | A2B6C_hP9_162_d_k_a |
| Strukturbericht designation | : | $I1_{3}$ |
| Pearson symbol | : | hP9 |
| Space group number | : | 162 |
| Space group symbol | : | $P\bar{3}1m$ |
| AFLOW prototype command | : | aflow --proto=A2B6C_hP9_162_d_k_a --params=$a$,$c/a$,$x_{3}$,$z_{3}$ |
Other compounds with this structure
- CaCl2 · (H2O)6, CaBr2 · (H2O)6, SrBr2 · (H2O)6, CaI2 · (H2O)6, SrI2 · (H2O)6, and BaI2 · (H2O)6
- (Hermann, 1937) gives this the Strukturbericht designation $I1_{3}$, but gives the prototype as K2Pt(SCN)6. As we discussed on the K2Pt(SCN)6 ($H6_{3}$) page, the difference between these two structures is significant, so we will use the original $H6_{3}$ designation for K2Pt(SCN)6, and $I1_{3}$ for SrCl2 · (H2O)6.
- In any case, (Aagon, 1986) and others have shown that the correct space group of this structure is $P321$ #150. We discuss the corrected structure on the SrCl2 · (H2O)6 page.
- Using the notation of (Gottfried, 1937) this could also be designated the $J1_{3}$ structure. That designation was never used in any Strukturbericht volume, so we will use $I1_{3}$ here.
- The positions of the hydrogen atoms in the water molecules were not determined, so we only provide the positions of the oxygen atoms (labeled as H2O).
Trigonal 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} & & \text{Lattice Coordinates} & & \text{Cartesian Coordinates} &\text{Wyckoff Position} & \text{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(1a\right) & \text{Sr} \\ \mathbf{B}_{2} & = & \frac{1}{3} \, \mathbf{a}_{1} + \frac{2}{3} \, \mathbf{a}_{2} + \frac{1}{2} \, \mathbf{a}_{3} & = & \frac{1}{2}a \, \mathbf{\hat{x}} + \frac{1}{2\sqrt{3}}a \, \mathbf{\hat{y}} + \frac{1}{2}c \, \mathbf{\hat{z}} & \left(2d\right) & \text{Cl} \\ \mathbf{B}_{3} & = & \frac{2}{3} \, \mathbf{a}_{1} + \frac{1}{3} \, \mathbf{a}_{2} + \frac{1}{2} \, \mathbf{a}_{3} & = & \frac{1}{2}a \, \mathbf{\hat{x}}- \frac{1}{2\sqrt{3}}a \, \mathbf{\hat{y}} + \frac{1}{2}c \, \mathbf{\hat{z}} & \left(2d\right) & \text{Cl} \\ \mathbf{B}_{4} & = & x_{3} \, \mathbf{a}_{1} + z_{3} \, \mathbf{a}_{3} & = & \frac{1}{2}x_{3}a \, \mathbf{\hat{x}}-\frac{\sqrt{3}}{2}x_{3}a \, \mathbf{\hat{y}} + z_{3}c \, \mathbf{\hat{z}} & \left(6k\right) & \text{H$_{2}$O} \\ \mathbf{B}_{5} & = & x_{3} \, \mathbf{a}_{2} + z_{3} \, \mathbf{a}_{3} & = & \frac{1}{2}x_{3}a \, \mathbf{\hat{x}} + \frac{\sqrt{3}}{2}x_{3}a \, \mathbf{\hat{y}} + z_{3}c \, \mathbf{\hat{z}} & \left(6k\right) & \text{H$_{2}$O} \\ \mathbf{B}_{6} & = & -x_{3} \, \mathbf{a}_{1}-x_{3} \, \mathbf{a}_{2} + z_{3} \, \mathbf{a}_{3} & = & -x_{3}a \, \mathbf{\hat{x}} + z_{3}c \, \mathbf{\hat{z}} & \left(6k\right) & \text{H$_{2}$O} \\ \mathbf{B}_{7} & = & -x_{3} \, \mathbf{a}_{2}-z_{3} \, \mathbf{a}_{3} & = & -\frac{1}{2}x_{3}a \, \mathbf{\hat{x}}-\frac{\sqrt{3}}{2}x_{3}a \, \mathbf{\hat{y}}-z_{3}c \, \mathbf{\hat{z}} & \left(6k\right) & \text{H$_{2}$O} \\ \mathbf{B}_{8} & = & -x_{3} \, \mathbf{a}_{1}-z_{3} \, \mathbf{a}_{3} & = & -\frac{1}{2}x_{3}a \, \mathbf{\hat{x}} + \frac{\sqrt{3}}{2}x_{3}a \, \mathbf{\hat{y}}-z_{3}c \, \mathbf{\hat{z}} & \left(6k\right) & \text{H$_{2}$O} \\ \mathbf{B}_{9} & = & x_{3} \, \mathbf{a}_{1} + x_{3} \, \mathbf{a}_{2}-z_{3} \, \mathbf{a}_{3} & = & x_{3}a \, \mathbf{\hat{x}}-z_{3}c \, \mathbf{\hat{z}} & \left(6k\right) & \text{H$_{2}$O} \\ \end{array} \]References
- Z. Hermann, Über die Struktur des Strontiumchlorid–Hexahydrats, Z. Anorg. Allg. Chem. 187, 231–236 (1930), doi:10.1002/zaac.19301870121.
- P. A. Agron and W. R. Busing, Calcium and strontium dichloride hexahydrates by neutron diffraction, Acta Crystallogr. C 42, 141–143 (1986), doi:10.1107/S0108270186097007.
- C. Gottfried and F. Schossberger, eds., Strukturbericht Band III 1933–1935 (Akademische Verlagsgesellschaft M. B. H., Leipzig, 1937).
Found in
- C. Hermann, O. Lohrmann, and H. Philipp, eds., Strukturbericht Band II 1928–1932 (Akademische Verlagsgesellschaft M. B. H., Leipzig, 1937).