Research/Sitter/MAGNDATA / 1.52_CaFe2As2.mcif

CaFe₂As₂

MAGNDATA entry 1.52 · source

antiferromagnet

No net magnetisation, and up and down sublattices are related by a shift or by inversion, so the bands stay spin-degenerate: a conventional antiferromagnet.

Spin group ¹m¹m¹m × ²1: each symmetry marked ¹ keeps every spin, ² swaps up and down.

ordered ≤ 173 K (−100 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 11 properties

Magnetic group	C_A m c a BNS 64.480
Point group	mmm1′
Parent space group	I 4/m m m No. 139
Spins	collinear · net moment 0 μ_B per cell
Propagation	[1/2 1/2 0] 1k
Cell	a 11.664 · b 5.506 · c 5.45 Å · α 90° · β 90° · γ 90°
Transition	173 K (−100 °C)
Measured at	10 K
Magnetic ions	Fe
Largest moment component	0.8 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 C_A m c a →

Atom sites · 3 sites · CSV

site	element	x	y	z	m_a	m_b	m_c	\|m\| (μ_B)
Ca	Ca	0	0	0
Fe	Fe	0.25	0.25	0.25	0	−0.8	0	0.8
As	As	0.3664	0	0

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

A.I. Goldman et al. PHYSICAL REVIEW B (2008) · doi:10.1103/physrevb.78.100506

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 1.52_CaFe2As2.mcif from MAGNDATA · entry page

sha256 of this copy: ca91b8d66a1152310719491b7323cdfab2b73eb4d1e094db08ce2c61609a27fe
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 1.52_CaFe2As2.mcif.