Crystal Lab › AB₂ and A₂B
Cadmium chloride CdCl₂
Layered AB₂, 6:3 · space group R-3m (No. 166) · Z = 3
Unit cell
- Lattice constants
- a = 3.850 Å, b = 3.850 Å, c = 17.460 Å; α = 90°, β = 90°, γ = 120°
- Cell volume
- 224.1 ų
- Atoms in the cell
- 9 (Cd 3, Cl 6)
- Formula units Z
- 3
- Calculated density
- 4.07 g cm⁻³
- Shortest contact
- 2.657 Å
Coordination
- Cd
- CN 6 at 2.66 Å (6 Cl)
- Cl
- CN 3 at 2.66 Å (3 Cd)
About the structure
- The ccp analogue of CdI₂: ccp array of Cl⁻ with Cd²⁺ in alternate layers of octahedral holes.
- Hexagonal cell shown (3 layers); the rhombohedral cell is smaller.
- MnCl₂, FeCl₂, CoCl₂, NiCl₂, MgCl₂ share this structure.
Atom positions (fractional, one cell)
| Atom | x | y | z |
|---|---|---|---|
| Cd | 0.0000 | 0.0000 | 0.0000 |
| Cd | 0.6667 | 0.3333 | 0.3333 |
| Cd | 0.3333 | 0.6667 | 0.6667 |
| Cl | 0.0000 | 0.0000 | 0.2500 |
| Cl | 0.6667 | 0.3333 | 0.5833 |
| Cl | 0.3333 | 0.6667 | 0.9167 |
| Cl | 0.0000 | 0.0000 | 0.7500 |
| Cl | 0.6667 | 0.3333 | 0.0833 |
| Cl | 0.3333 | 0.6667 | 0.4167 |
Z, coordination numbers, distances, density and packing on this page are computed from these coordinates.