Skip to content

Crystal Lab › Prototype structures › Tetragonal

Nb₄CoSi

Tetragonal · space group P4/mcc (No. 124) · Pearson tP12

Symmetry elements and Wyckoff positions (interactive)

Nb₄CoSi in P4/mcc

Setting
Loading the group…
x = 0.10, y = 0.17, z = 0.08

Unit cell

Lattice constants
a = 6.189 Å, b = 6.189 Å, c = 5.053 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
193.5 ų
Atoms in the conventional cell
12 (Co 2, Si 2, Nb 8)
Formula units Z
2
Pearson symbol
tP12 — tetragonal, primitive lattice, 12 atoms per conventional cell
Symmetry operations
16 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Co1Co2a20.00000.00000.2500
Si3Si2c20.50000.50000.2500
Nb2Nb8m80.16200.66200.0000

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 12 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

AB4C_tP12_124_a_m_c-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol tP12, then the space-group number 124, then the Wyckoff letters occupied by each element in turn (Co: 2a; Si: 2c; Nb: 8m). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Nb₄FeSi, Nb₄NiSi <!--beginning with an

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB4C_tP12_124_a_m_c-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.

 ·  Space group P4/mcc (3 prototypes)  ·  All prototypes  ·  Room Temperature NbTe₄ →