Possible δ-Gd₂Si₂O₇ Gd₂O₇Si₂

Unit cell

Lattice constants

a = 13.870 Å, b = 5.073 Å, c = 8.330 Å; α = 90.00°, β = 90.00°, γ = 90.00°

Cell volume

586.1 ų

Atoms in the conventional cell

44 (Gd 8, O 28, Si 8)

Formula units Z

4

Pearson symbol

oP44 — orthorhombic, primitive lattice, 44 atoms per conventional cell

Symmetry operations

4 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 44 atoms drawn above are these sites multiplied by all 4 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

A2B7C2_oP44_33_2a_7a_2a-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oP44, then the space-group number 33, then the Wyckoff letters occupied by each element in turn (Gd: 4a; Gd: 4a; O: 4a; O: 4a; O: 4a; O: 4a; O: 4a; O: 4a; O: 4a; Si: 4a; Si: 4a). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

δ-Ho₂O₇Si₂, δ-Dy₂O₇Si₂, δ-Y₂O₇Si₂ <!--beginning with an

Note: Candidate \delta-RE₂Si₂O₇.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A2B7C2_oP44_33_2a_7a_2a-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.