Na$_{2}$HgO$_{2}$ Structure: AB2C2_tI10_139_a_e_e-001
| Prototype | HgNa$_{2}$O$_{2}$ |
| AFLOW prototype label | AB2C2_tI10_139_a_e_e-001 |
| ICSD | 25511 |
| Pearson symbol | tI10 |
| Space group number | 139 |
| Space group symbol | $I4/mmm$ |
| AFLOW prototype command |
aflow --proto=AB2C2_tI10_139_a_e_e-001
--params=$a, \allowbreak c/a, \allowbreak z_{2}, \allowbreak z_{3}$ |
Other compounds with this structure
Cs$_{2}$HgO$_{2}$, Li$_{2}$HgO$_{2}$, Rb$_{2}$HgO$_{2}$, U$_{2}$IrC$_{2}$, U$_{2}$RuC$_{2}$
- (Hoppe, 1964) give the space group as $I422$ #97, but the Wyckoff positions they use are consistent with $I4/mmm$ #139, so we use the higher symmetry space group.
\[ \begin{array}{ccc}
\mathbf{a_{1}}&=&- \frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}\\\mathbf{a_{2}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}- \frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}\\\mathbf{a_{3}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}- \frac{1}{2}c \,\mathbf{\hat{z}}
\end{array}\]
Basis vectors
| Lattice coordinates | Cartesian coordinates | Wyckoff position | Atom type | |||
|---|---|---|---|---|---|---|
| $\mathbf{B_{1}}$ | = | $0$ | = | $0$ | (2a) | Hg I |
| $\mathbf{B_{2}}$ | = | $z_{2} \, \mathbf{a}_{1}+z_{2} \, \mathbf{a}_{2}$ | = | $c z_{2} \,\mathbf{\hat{z}}$ | (4e) | Na I |
| $\mathbf{B_{3}}$ | = | $- z_{2} \, \mathbf{a}_{1}- z_{2} \, \mathbf{a}_{2}$ | = | $- c z_{2} \,\mathbf{\hat{z}}$ | (4e) | Na I |
| $\mathbf{B_{4}}$ | = | $z_{3} \, \mathbf{a}_{1}+z_{3} \, \mathbf{a}_{2}$ | = | $c z_{3} \,\mathbf{\hat{z}}$ | (4e) | O I |
| $\mathbf{B_{5}}$ | = | $- z_{3} \, \mathbf{a}_{1}- z_{3} \, \mathbf{a}_{2}$ | = | $- c z_{3} \,\mathbf{\hat{z}}$ | (4e) | O I |
References
- R. Hoppe and H.-J. Rohrborn, Oxomercurate(II) der Alkalimetalle, M$_{2}$HgO$_{2}$, Zeitschrift für anorganische und allgemeine Chemie 329, 110–122 (1964), doi:10.1002/zaac.19643290115.
Prototype Generator
aflow --proto=AB2C2_tI10_139_a_e_e --params=$a,c/a,z_{2},z_{3}$