Skip to content

Crystal Lab › Prototype structures › Orthorhombic

Ferroelectric NaNO₂ (F5₅)

Orthorhombic · space group Imm2 (No. 44) · Pearson oI8 · Strukturbericht F55 · mineral: sodium nitrite

Symmetry elements and Wyckoff positions (interactive)

Ferroelectric NaNO₂ (F5₅) in Imm2

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

Unit cell

Lattice constants
a = 5.384 Å, b = 3.560 Å, c = 5.563 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
106.6 ų
Atoms in the conventional cell
8 (N 2, Na 2, O 4)
Formula units Z
2
Pearson symbol
oI8 — orthorhombic, body-centred lattice, 8 atoms per conventional cell
Symmetry operations
8 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
N1N2a20.00000.00000.8800
Na2Na2a20.00000.00000.4147
O3O4c40.80590.00000.0000

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 8 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

ABC2_oI8_44_a_a_c-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oI8, then the space-group number 44, then the Wyckoff letters occupied by each element in turn (N: 2a; Na: 2a; O: 4c). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

AgNO₃ (F5₁₂) <!--beginning with an

Note: F5₅, Sodium Nitrite.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry ABC2_oI8_44_a_a_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.

← Hemimorphite (Zn₄Si₂O₇(OH)₂ cdotH₂O, S2₂)  ·  Space group Imm2 (5 prototypes)  ·  All prototypes  ·  AgNO₂ (F5₁₂) →