Research/Sitter/MAGNDATA / 1.1.57_ErNi2B2C.mcif

ErNi₂B₂C

MAGNDATA entry 1.1.57 · 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 ≤ 6.8 K (−266 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 11 properties

Magnetic group	Immm1′(α00)00ss
Point group	mmm1′
Parent space group	I 4/m m m No. 139
Repeats every	1.81 cells along a (not a whole number: that's what incommensurate means)
Propagation	[0.5526 0 0] 1k
Cell	a 3.5019 · b 3.5019 · c 10.558 Å · α 90° · β 90° · γ 90°
Transition	6.8 K (−266 °C)
Measured at	2 K
Magnetic ions	Er, Ni
Largest moment component	7.8 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 Immm1′(α00)00ss →

Atom sites · 4 sites · CSV

site	element	x	y	z
Er1	Er	0	0	0
Ni1	Ni	0.5	0	0.25
B1	B	0	0	0.3597
C1	C	0.5	0.5	0

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

S.K. Sinha et al. PHYSICAL REVIEW B (1995) · doi:10.1103/PhysRevB.51.681

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 1.1.57_ErNi2B2C.mcif from MAGNDATA · entry page

sha256 of this copy: d8077206e27bdd0c09aa3a34d278d0425cb967df4389bb6b27e646a75379814c
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 1.1.57_ErNi2B2C.mcif.