Crystal Lab › Prototype structures › Orthorhombic
PdSn₄
Orthorhombic · space group Ccce (No. 68) · Pearson oC20
Symmetry elements and Wyckoff positions (interactive)
PdSn₄ in Ccce
SettingUnit cell
- Lattice constants
- a = 11.445 Å, b = 6.442 Å, c = 6.389 Å; α = 90.00°, β = 90.00°, γ = 90.00°
- Cell volume
- 471.1 ų
- Atoms in the conventional cell
- 20 (Pd 4, Sn 16)
- Formula units Z
- 4
- Pearson symbol
- oC20 — orthorhombic, base-centred lattice, 20 atoms per conventional cell
- Symmetry operations
- 16 per cell
Crystallographic sites
| Site | Element | Wyckoff | Multiplicity | x | y | z |
|---|---|---|---|---|---|---|
| Pd1 | Pd | 4a | 4 | 0.0000 | 0.2500 | 0.2500 |
| Sn2 | Sn | 16i | 16 | 0.8733 | 0.9187 | 0.0801 |
The multiplicity and the Wyckoff letter say how many copies of the site the group makes in one cell and on which kind of symmetry element the site sits; the 20 atoms drawn above are these sites multiplied by all 16 operations. Press Wyckoff under Colour to see the sites, and tick a symmetry element on the left to see which atoms lie on it.
How to read the label
AB4_oC20_68_a_i-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oC20, then the space-group number 68, then the Wyckoff letters occupied by each element in turn (Pd: 4a; Sn: 16i). Two structures with the same label are the same arrangement with different cell parameters or coordinates.
Source
Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB4_oC20_68_a_i-001 (M. J. Mehl et al., Comput. Mater. Sci. 136, S1 (2017); D. Hicks et al., ibid. 161, S1 (2019) and 199, 110450 (2021); S. Eckert et al., ibid. 240, 112988 (2024)). Symmetry elements, Wyckoff assignment and the diagram are computed on this page from the group operations.