Research/Sitter/MAGNDATA / 1.1.162_NdB4.mcif

NdB₄

MAGNDATA entry 1.1.162 · 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 ≤ 17.5 K (−256 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 11 properties

Magnetic group	P1′(αβγ)0
Point group	1′
Parent space group	P 4/m b m No. 127
Repeats every	2.5 cells along c (not a whole number: that's what incommensurate means)
Propagation	[0.1421 0.1421 0.4] 1k
Cell	a 7.2139 · b 7.2139 · c 4.0977 Å · α 90° · β 90° · γ 90°
Transition	17.5 K (−256 °C)
Measured at	5.5 K
Magnetic ions	Nd
Largest moment component	1.092 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 P1′(αβγ)0 →

Atom sites · 10 sites · CSV

site	element	x	y	z	m_a	m_b	m_c	\|m\| (μ_B)
Nd1_1	Nd	0.3167	0.8167	0	1.092	−1.092	0.616	1.6626
Nd1_2	Nd	0.8167	0.6833	0	−1.092	−1.092	−0.616	1.6626
B1_1	B	0	0	0.2039
B1_2	B	0.5	0.5	0.7961
B2_1	B	0.0873	0.5873	0.5
B2_2	B	0.5873	−0.0873	0.5
B3_1	B	0.1756	0.0386	0.5
B3_2	B	0.6756	0.4613	0.5
B3_3	B	0.4613	0.3244	0.5
B3_4	B	−0.0386	0.1756	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

D.D. Khalyavin et al. PHYSICAL REVIEW B (2024) · doi:10.1103/PhysRevB.109.L220411

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 1.1.162_NdB4.mcif from MAGNDATA · entry page

sha256 of this copy: 4005724594e2eaa2997af4d0f8bdb5f95e2d15bcb787455d3c535603fbccf5ce
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 1.1.162_NdB4.mcif.