Research/Sitter/MAGNDATA / 0.303_BaCrF5.mcif

BaCrF₅

MAGNDATA entry 0.303 · 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 ¹m²m²m: each symmetry marked ¹ keeps every spin, ² swaps up and down.

ordered ≤ 3.4 K (−270 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 10 properties

Magnetic group	P 2₁′ 2₁′ 2₁ BNS 19.27
Parent space group	P 2₁ 2₁ 2₁ No. 19
Spins	collinear · 2 nodal planes · net moment 0 μ_B per cell
Propagation	[0 0 0] 1k
Cell	a 13.938 · b 5.711 · c 4.947 Å · α 90° · β 90° · γ 90°
Transition	3.4 K (−270 °C)
Measured at	2.2 K
Magnetic ions	Cr
Largest moment component	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 2₁′ 2₁′ 2₁ →

Atom sites · 7 sites · CSV

site	element	x	y	z	m_a	m_b	m_c	\|m\| (μ_B)
Ba1	Ba	0.0923	0.0899	0.0178
F1	F	0.2667	0.1439	0.7809
F2	F	0.4211	0.1854	0.0871
F3	F	0.0918	0.3481	0.5564
F4	F	0.0807	0.599	0.129
F5	F	0.2479	0.3873	0.2326
Cr1	Cr	0.165	0.6026	0.4247	0	0	1	1

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

H. Holler et al. Z. fur Naturforschung B (1982)

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 0.303_BaCrF5.mcif from MAGNDATA · entry page

sha256 of this copy: e8ab3a42bb802b37840f9228d5a25648e904340af2f4f2ca143b2be0332808ed
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 0.303_BaCrF5.mcif.