Research/Sitter/MAGNDATA / 0.241_Y2Cu2O5.mcif

Y₂Cu₂O₅

MAGNDATA entry 0.241 · 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 ≤ 13 K (−260 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 10 properties

Magnetic group	P n a 2₁ BNS 33.144
Parent space group	P n a 2₁ No. 33
Spins	collinear · 2 nodal planes · net moment 0 μ_B per cell
Propagation	[0 0 0] 1k
Cell	a 10.796 · b 3.494 · c 12.4546 Å · α 90° · β 90° · γ 90°
Transition	13 K (−260 °C)
Measured at	1.5 K
Magnetic ions	Cu
Largest moment component	1.1 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 n a 2₁ →

Atom sites · 9 sites · CSV

site	element	x	y	z	m_a	m_b	m_c	\|m\| (μ_B)
Y1	Y	0.2067	0.231	0
Y2	Y	0.0406	0.232	0.3294
Cu1	Cu	0.9909	0.656	0.1123	0	−1.1	0	1.1
Cu2	Cu	0.2602	0.674	0.2151	0	−1.1	0	1.1
O1	O	0.1761	0.723	0.3487
O2	O	0.3262	0.733	0.0665
O3	O	0.123	0.314	0.165
O4	O	0.431	0.781	0.263
O5	O	0.4241	0.236	0.47

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. L. Garcia-Munoz et al. Phys. Rev. B (1991) · doi:10.1103/PhysRevB.44.4716

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 0.241_Y2Cu2O5.mcif from MAGNDATA · entry page

sha256 of this copy: 994e24da053b2877b09e6c4c612e65a6aec2f75156e36ad31f34aa1f60cabbe5
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 0.241_Y2Cu2O5.mcif.