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NH₄NO₃ I (G0₈)

Cubic · space group Pm-3m (No. 221) · Pearson cP2 · Strukturbericht G08

Symmetry elements and Wyckoff positions (interactive)

NH₄NO₃ I (G0₈) in Pm-3m

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

Unit cell

Lattice constants
a = 4.400 Å, b = 4.400 Å, c = 4.400 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
85.2 ų
Atoms in the conventional cell
2 (N 2)
Formula units Z
2
Pearson symbol
cP2 — cubic, primitive lattice, 2 atoms per conventional cell
Symmetry operations
48 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
NH1N1a10.00000.00000.0000
NO2N1b10.50000.50000.5000

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 2 atoms drawn above are these sites multiplied by all 48 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

AB_cP2_221_a_b-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol cP2, then the space-group number 221, then the Wyckoff letters occupied by each element in turn (N: 1a; N: 1b). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Note: G0₈, NH₄NO₃ I.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB_cP2_221_a_b-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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