Research/Sitter/MAGNDATA / 0.45_La2NiO4.mcif

La₂NiO₄

MAGNDATA entry 0.45 · source

d-wave altermagnet

No net magnetisation, yet the electron bands are spin-split: the up and down spin sublattices are related only by a rotation or mirror, never by a shift or inversion. d-wave: the splitting changes sign twice around the Fermi surface (2 nodal planes).

Spin group ²m¹m²m: each symmetry marked ¹ keeps every spin, ² swaps up and down.

ordered ≤ 80 K (−193 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 11 properties

Magnetic group	P c′ c′ n BNS 56.369
Point group	m′m′m
Parent space group	P 4₂/n c m No. 138
Spins	collinear · 2 nodal planes · net moment 0 μ_B per cell
Propagation	[0 0 0] 1k
Cell	a 5.4995 · b 5.4995 · c 12.5052 Å · α 90° · β 90° · γ 90°
Transition	80 K (−193 °C)
Measured at	4 K
Magnetic ions	Ni
Largest moment component	1.68 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 P c′ c′ n →

Atom sites · 5 sites · CSV

site	element	x	y	z	m_a	m_b	m_c	\|m\| (μ_B)
La1	La	−0.0072	−0.0072	0.3639
Ni1	Ni	0	0	0	1.68	0	0	1.68
O1	O	0.75	0.75	0.0155
O2	O	0.75	0.25	0
O3	O	0.0314	0.0314	0.1771

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. Rodriguez-Carvajal et al. J. Phys.: Condens. Matter (1991) · doi:10.1088/0953-8984/3/19/002

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 0.45_La2NiO4.mcif from MAGNDATA · entry page

sha256 of this copy: 8964097790b25ecfd84c9a3e3a7c1635a8d9baacda557a207508d46ccb6f487c
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 0.45_La2NiO4.mcif.