Research/Sitter/MAGNDATA / 0.1071_Fe2SiO4.mcif

Fe₂Si₁O₄

MAGNDATA entry 0.1071 · 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 ²m²m¹m: each symmetry marked ¹ keeps every spin, ² swaps up and down.

ordered ≤ 65.4 K (−208 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 11 properties

Magnetic group	P n m a . 1 BNS 62.441
Point group	mmm
Parent space group	P n m a No. 62
Spins	collinear · 2 nodal planes · net moment 0 μ_B per cell
Propagation	[0 0 0] 1k
Cell	a 4.81654 · b 10.44887 · c 6.08256 Å · α 90° · β 90° · γ 90°
Transition	65.4 K (−208 °C)
Measured at	40 K
Magnetic ions	Fe
Largest moment component	4.28 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 m a . 1 →

Atom sites · 6 sites · CSV

site	element	x	y	z	m_a	m_b	m_c	\|m\| (μ_B)
Fe1	Fe	0	0	0	0	0	2.38	2.38
Fe2	Fe	0.9859	0.2798	0.25	0	0	4.28	4.28
Si1	Si	0.4307	0.0972	0.25
O1	O	0.7687	0.092	0.25
O2	O	0.2088	0.4529	0.25
O3	O	0.2889	0.1658	0.4642

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

Evangelia K. Tripoliti et al. Mineralogical Magazine (2023) · doi:10.1180/mgm.2023.66

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 0.1071_Fe2SiO4.mcif from MAGNDATA · entry page

sha256 of this copy: 3ae667fd11aaf2609cba127147ec15aaadf185cc27af6cf4acd11680989fde67
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 0.1071_Fe2SiO4.mcif.

Fe2Si1O4

Symmetry

Source

Original file

Fe₂Si₁O₄