Skip to content

Crystal Lab › Prototype structures › Trigonal

Dolomite [MgCa(CO₃)₂, G1₁

Trigonal · space group R-3 (No. 148) · Pearson hR10 · Strukturbericht G11 · mineral: dolomite

Symmetry elements and Wyckoff positions (interactive)

Dolomite [MgCa(CO₃)₂, G1₁ in R-3

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

Unit cell

Lattice constants
a = 4.807 Å, b = 4.807 Å, c = 16.002 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
320.2 ų
Atoms in the conventional cell
30 (Ca 3, Mg 3, C 6, O 18)
Formula units Z
3
Pearson symbol
hR10 — hexagonal / trigonal, rhombohedral lattice, 10 atoms per conventional cell
Symmetry operations
18 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Ca2Ca3a30.00000.00000.0000
Mg3Mg3b30.00000.00000.5000
C1C6c60.00000.00000.2429
O4O18f180.58130.95010.9106

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 30 atoms drawn above are these sites multiplied by all 18 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

A2BCD6_hR10_148_c_a_b_f-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hR10, then the space-group number 148, then the Wyckoff letters occupied by each element in turn (Ca: 3a; Mg: 3b; C: 6c; O: 18f). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Note: G1₁, Dolomite.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A2BCD6_hR10_148_c_a_b_f-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.

← BaNi₂As₂O₈  ·  Space group R-3 (27 prototypes)  ·  All prototypes  ·  β-PdCl₂ — Cl₂Pd →