Spinel (Al₂MgO₄, H1₁)

Unit cell

Lattice constants

a = 8.083 Å, b = 8.083 Å, c = 8.083 Å; α = 90.00°, β = 90.00°, γ = 90.00°

Cell volume

528.1 ų

Atoms in the conventional cell

56 (Mg 8, Al 16, O 32)

Formula units Z

8

Pearson symbol

cF56 — cubic, face-centred lattice, 56 atoms per conventional cell

Symmetry operations

192 per cell

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 56 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

A2BC4_cF56_227_c_b_e-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol cF56, then the space-group number 227, then the Wyckoff letters occupied by each element in turn (Mg: 8b; Al: 16c; O: 32e). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Al₂CdS₄, Al₂CrS₄, Al₂ZnSe₄, Cd₂VS₄, Co₂NiS₄, Co₃Se₄, Cr₂CdTe₄, Cr₂CoS₄, Cr₂CuS₄, Cr₂CuSe₄, Cr₂CoO₄, Cr₂FeO₄, Cr₂FeS₄, Cr₂HgS₄, Cr₂MnS₄, Cr₂SeZn₄, Cr₂ZrCd₄, Cr₂ZrSe₄, Ga₂CoS₄, Fe₂NiO₄, In₂CaS₄, In₂CdSe₄, In₂CrS₄, In₂FeS₄, In₂HgS₄, In₂MgS₄, In₂MnS₄, In₂NiS₄, In₂ZrCd₄, Ir₂CuS₄, Lu₂FeS₄, Lu₂MgS₄, Lu₂MnS₄, Mg₂GeO₄, Mn₂ZnTe₄, Na₂WO₄, Ni₂FeS₄, Sc₂FeS₄, Sc₂MnS₄, Sc₂MnSe₄, Ti₂CuS₄, V₂LiO₄, V₂CuS₄, V₂ZnO₄, Yb₂FeS₄, Yb₂MnS₄, Co₃O₄, Co₃S₄, Fe₃O₄, Fe₃S₄ (greigite), Ni₃S₄ <!--beginning with an

Note: H1₁, Spinel.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A2BC4_cF56_227_c_b_e-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.