Research/Sitter/MAGNDATA / 1.1.126_GdNi2Si2.mcif

GdNi₂Si₂

MAGNDATA entry 1.1.126 · source

incommensurate spin-density wave

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 spin-density wave: the size of the spin swells and shrinks as you move along.

ordered ≤ 14.5 K (−259 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 11 properties

Magnetic group	I2/m1′(α,0,γ)00s
Point group	2/m1′
Parent space group	I 4/m m m No. 139
Repeats every	0.83 cells along a (not a whole number: that's what incommensurate means)
Propagation	[1.207 0 0.903] 1k
Cell	a 3.973 · b 3.973 · c 9.583 Å · α 90° · β 90° · γ 90°
Transition	14.5 K (−259 °C)
Measured at	4.2 K
Magnetic ions	Gd
Largest moment component	8.9 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 I2/m1′(α,0,γ)00s →

Atom sites · 3 sites · CSV

site	element	x	z
Gd1_1	Gd	0	0
Ni1_1	Ni	0.5	0.75
Si1_1	Si	0	0.366

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

J. M. Barandiaran et al. Journal of Magnetism and Magnetic Materials (1988) · doi:10.1016/0304-8853(88)90299-5

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 1.1.126_GdNi2Si2.mcif from MAGNDATA · entry page

sha256 of this copy: 2210e5c433e854fa0e5e6112b2e03a476c5410b5a351f2debd5c63e00b1566b9
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 1.1.126_GdNi2Si2.mcif.