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Ta₃Ti₁₃ (BCC SQS-16)

Orthorhombic · space group Amm2 (No. 38) · Pearson oC32

Symmetry elements and Wyckoff positions (interactive)

Ta₃Ti₁₃ (BCC SQS-16) in Amm2

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

Unit cell

Lattice constants
a = 6.542 Å, b = 9.252 Å, c = 9.252 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
560.0 ų
Atoms in the conventional cell
32 (Ta 6, Ti 26)
Formula units Z
2
Pearson symbol
oC32 — orthorhombic, base-centred lattice, 32 atoms per conventional cell
Symmetry operations
8 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Ta1Ta2a20.00000.00000.5000
Ti3Ti2a20.00000.00000.0000
Ti4Ti2b20.50000.00000.5000
Ti5Ti2b20.50000.00000.0000
Ta2Ta4c40.75000.00000.2500
Ti6Ti4c40.75000.00000.7500
Ti7Ti4d40.00000.75000.7500
Ti8Ti4e40.50000.75000.7500
Ti9Ti8f80.75000.75000.0000

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 32 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

A3B13_oC32_38_ac_a2bcdef-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oC32, then the space-group number 38, then the Wyckoff letters occupied by each element in turn (Ta: 2a; Ti: 2a; Ti: 2b; Ti: 2b; Ta: 4c; Ti: 4c; Ti: 4d; Ti: 4e; Ti: 8f). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Note: BCC SQS-16.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A3B13_oC32_38_ac_a2bcdef-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.

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