Crystal Lab › Prototype structures › Tetragonal
K₅Fe₄Ag₆Te₁₀
Tetragonal · space group I4 (No. 79) · Pearson tI50
Symmetry elements and Wyckoff positions (interactive)
K₅Fe₄Ag₆Te₁₀ in I4
SettingUnit cell
- Lattice constants
- a = 9.786 Å, b = 9.786 Å, c = 14.933 Å; α = 90.00°, β = 90.00°, γ = 90.00°
- Cell volume
- 1430.0 ų
- Atoms in the conventional cell
- 50 (K 10, Te 20, Ag 12, Fe 8)
- Formula units Z
- 2
- Pearson symbol
- tI50 — tetragonal, body-centred lattice, 50 atoms per conventional cell
- Symmetry operations
- 8 per cell
Crystallographic sites
| Site | Element | Wyckoff | Multiplicity | x | y | z |
|---|---|---|---|---|---|---|
| K4 | K | 2a | 2 | 0.0000 | 0.0000 | 0.1472 |
| Te6 | Te | 2a | 2 | 0.0000 | 0.0000 | 0.7851 |
| Te7 | Te | 2a | 2 | 0.0000 | 0.0000 | 0.5184 |
| Ag1 | Ag | 4b | 4 | 0.0000 | 0.5000 | 0.4170 |
| Ag2 | Ag | 8c | 8 | 0.5874 | 0.2988 | 0.4103 |
| Fe3 | Fe | 8c | 8 | 0.5978 | 0.8044 | 0.1680 |
| K5 | K | 8c | 8 | 0.3992 | 0.6946 | 0.9123 |
| Te8 | Te | 8c | 8 | 0.3030 | 0.8769 | 0.0274 |
| Te9 | Te | 8c | 8 | 0.5915 | 0.7886 | 0.8000 |
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 50 atoms drawn above are these sites multiplied by all 8 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
A6B4C5D10_tI50_79_bc_c_ac_2a2c-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol tI50, then the space-group number 79, then the Wyckoff letters occupied by each element in turn (K: 2a; Te: 2a; Te: 2a; Ag: 4b; Ag: 8c; Fe: 8c; K: 8c; Te: 8c; Te: 8c). 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 A6B4C5D10_tI50_79_bc_c_ac_2a2c-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.