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β-Alum [Al(NH₃CH₃)₂(SO₄)₂ cdot 12H₂O, H4₁₄]

Cubic · space group Pa-3 (No. 205) · Pearson cP252 · Strukturbericht H414 · mineral: beta-alum

Symmetry elements and Wyckoff positions (interactive)

β-Alum [Al(NH₃CH₃)₂(SO₄)₂ cdot 12H₂O, H4₁₄] in Pa-3

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

Unit cell

Lattice constants
a = 12.314 Å, b = 12.314 Å, c = 12.314 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
1867.2 ų
Atoms in the conventional cell
252 (Al 4, C 8, N 8, O 80, S 8, H 144)
Formula units Z
4
Pearson symbol
cP252 — cubic, primitive lattice, 252 atoms per conventional cell
Symmetry operations
24 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Al1Al4a40.00000.00000.0000
C2C8c80.45010.45010.4501
N9N8c80.51560.51560.5156
O10O8c80.23410.23410.2341
S14S8c80.30220.30220.3022
H3H24d240.38510.50720.4134
H4H24d240.08370.53630.0275
H5H24d240.54230.20180.4728
H6H24d240.41320.18460.4502
H7H24d240.21430.49410.1944
H8H24d240.21480.61030.1697
O11O24d240.69110.75300.0914
O12O24d240.85210.98100.0185
O13O24d240.04190.13730.2975

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 252 atoms drawn above are these sites multiplied by all 24 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

AB2C36D2E20F2_cP252_205_a_c_6d_c_c3d_c-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol cP252, then the space-group number 205, then the Wyckoff letters occupied by each element in turn (Al: 4a; C: 8c; N: 8c; O: 8c; S: 8c; H: 24d; H: 24d; H: 24d; H: 24d; H: 24d; H: 24d; O: 24d; O: 24d; O: 24d). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

AlCs(SO₄)₂ cdot 12H₂O <!--beginning with an

Note: \beta-Alum.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB2C36D2E20F2_cP252_205_a_c_6d_c_c3d_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.

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