η-carbide (Fe₃W₃C, E9₃)

Unit cell

Lattice constants

a = 11.087 Å, b = 11.087 Å, c = 11.087 Å; α = 90.00°, β = 90.00°, γ = 90.00°

Cell volume

1362.8 ų

Atoms in the conventional cell

112 (C 16, Fe 48, W 48)

Formula units Z

16

Pearson symbol

cF112 — cubic, face-centred lattice, 112 atoms per conventional cell

Symmetry operations

192 per cell

Calculated density

14.25 g cm⁻³ (cell contents ÷ cell volume, standard atomic weights)

Crystallographic sites

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 112 atoms drawn above are these sites multiplied by all 192 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

AB3C3_cF112_227_c_de_f-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol cF112, then the space-group number 227, then the Wyckoff letters occupied by each element in turn (C: 16c; Fe: 16d; Fe: 32e; W: 48f). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Cr₃Nb₃C, Fe₃Mo₃C, Fe₄Mo₂C, Fe₆W₆C, Hf₅Zn₃C, Mn₃Mo₃C, Mn₃Ni₃Si, Mn₃Ti₃O, Mn₃W₃C, Mo₃Ni₃C, Mo₄Co₂C, Mo₄Co₂C, Mo₄Ni₂C, Nb₂ZnC_x, Nb₂ZnC_x, Nb₄Rh₂C_x, Ni₃W₃C, Ni₅W₆C, Ti₂ZnC_x, Ti₂ZnC_x, Ti₄Pt₂O, Ti₄Rh₂O, V₃Zr₃C, W₃Co₃C, W₄Co₂C, Zn₂ZnN_x, Zr₂ZnC_x, Zr₄Pt₂O

Note: E9₃, \eta-Carbide.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB3C3_cF112_227_c_de_f-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.