Research/Sitter/MAGNDATA / 1.1.103_GdBe13.mcif

GdBe₁₃

MAGNDATA entry 1.1.103 · source

incommensurate spiral

Incommensurate: the magnetic pattern repeats every so many cells, but not a whole number of them, so it never lines up with the crystal lattice. Here it's a spiral: the spin direction rotates as you move along.

ordered ≤ 27 K (−246 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 11 properties

Magnetic group	I4221′(0,0,γ)q00s
Point group	4221′
Parent space group	F m 3 c No. 226
Repeats every	3.52 cells along c (not a whole number: that's what incommensurate means)
Propagation	[0 0 0.284] 1k
Cell	a 10.25 · b 10.25 · c 10.25 Å · α 90° · β 90° · γ 90°
Transition	27 K (−246 °C)
Measured at	3 K
Magnetic ions	Gd
Largest moment component	6.6 μ_B
Method	NPD

Symmetry

Stereogram of the magnetic point group: each operation applied to one direction. Filled = upper hemisphere, ring = lower; red operations include time reversal. Lines are mirrors; polygons are 2/3/4/6-fold axes; the centre ring is inversion.

Every structure in I4221′(0,0,γ)q00s →

Atom sites · 6 sites · CSV

site	element	x	y	z
Gd1_1	Gd	0.75	0.25	0.25
Gd1_2	Gd	0.75	0.25	0.75
Be1_1	Be	0	0	0.5
Be2_1	Be	0	0.322	0.615
Be2_2	Be	0.615	0	0.678
Be2_3	Be	0.678	0.885	0.5

Incommensurate: the moments are modulated; the picture evaluates each atom's Fourier series at its own phase.

Moment components are along the crystal axes a, b, c (μ_B), as magCIF writes them. Symmetry generates the rest of the cell from these sites.

Source

F Vigneron et al. J. Phys. F: Met. Phys. (1982) · doi:10.1088/0305-4608/12/1/019

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 1.1.103_GdBe13.mcif from MAGNDATA · entry page

sha256 of this copy: 1a84d4f76b7655d2007d35a53c4adadf6ff8d3503bda64eddbd8dc4b0e84cfce
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 1.1.103_GdBe13.mcif.