Research/Sitter/MAGNDATA / 1.1.89_SrMnGe2O6.mcif

SrMnGe₂O₆

MAGNDATA entry 1.1.89 · source

incommensurate spiral

Incommensurate: the magnetic pattern repeats every so many cells, but not a whole number of them, so it never lines up with the crystal lattice. Here it's a spiral: the spin direction rotates as you move along.

ordered ≤ 4.4 K (−269 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 11 properties

Magnetic group	C2/c1′(0β0)s0s
Point group	2/m1′
Parent space group	C 2/c No. 15
Repeats every	2.62 cells along b (not a whole number: that's what incommensurate means)
Propagation	[0 0.381 0] 1k
Cell	a 10.3559 · b 9.3903 · c 5.5133 Å · α 90° · β 104.651° · γ 90°
Transition	4.36 K (−269 °C)
Measured at	4.1 K
Magnetic ions	Mn
Largest moment component	2.019 μ_B
Method	NSD

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 C2/c1′(0β0)s0s →

Atom sites · 6 sites · CSV

site	element	x	y	z
Sr1	Sr	0	0.3085	0.25
Mn1	Mn	0	0.9076	0.25
Ge1	Ge	0.2824	0.0955	0.2193
O1	O	0.1111	0.0874	0.1396
O2	O	0.3578	0.2547	0.3181
O3	O	0.3535	0.0218	0.9812

Incommensurate: the moments are modulated; the picture evaluates each atom's Fourier series at its own phase.

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

C.V. Colin et al. PHYSICAL REVIEW B (2020) · doi:10.1103/PhysRevB.101.235109

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 1.1.89_SrMnGe2O6.mcif from MAGNDATA · entry page

sha256 of this copy: ea909ce2f497724c7649f717eaef4336e2d7eddcc8b1661937a8ac1c0800e816
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 1.1.89_SrMnGe2O6.mcif.