Research/Sitter/MAGNDATA / 1.1.132_NdCu2.mcif

NdCu₂

MAGNDATA entry 1.1.132 · 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 ≤ 4.1 K (−269 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 11 properties

Magnetic group	Imma1′(0,0,γ)00ss
Point group	mmm1′
Parent space group	I m m a No. 74
Repeats every	1.67 cells along a (not a whole number: that's what incommensurate means)
Propagation	[0.6 0 0] 1k
Cell	a 4.37 · b 6.98 · c 7.37 Å · α 90° · β 90° · γ 90°
Transition	4.1 K (−269 °C)
Measured at	1.8 K
Magnetic ions	Nd
Largest moment component	2.32 μ_B
Method	NPD and NSD

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 Imma1′(0,0,γ)00ss →

Atom sites · 2 sites · CSV

site	element	x	y	z	m_a	m_b	m_c	\|m\| (μ_B)
Cu1	Cu	0	0.0506	0.167
Nd1	Nd	0	0.25	0.5404

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

M. Loewenhaupt et al. Z. Phys. B (1995) · doi:10.1007/BF01313846

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 1.1.132_NdCu2.mcif from MAGNDATA · entry page

sha256 of this copy: c1299abca82ddfcaa018647f48f1afd1a0f3c75d505d6bb36a8bc9cca1142ca6
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 1.1.132_NdCu2.mcif.