Research/Sitter/MAGNDATA / 1.1.100_RbAg2Fe(VO4)2.mcif

RbAg₂Fe(VO₄)₂

MAGNDATA entry 1.1.100 · 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 ≤ 3.2 K (−270 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 11 properties

Magnetic group	P31′(1/3,1/3,γ)ts
Point group	31′
Parent space group	P 3 No. 147
Repeats every	2.69 cells along c (not a whole number: that's what incommensurate means)
Propagation	[0.33333 0.33333 0.3724] 1k
Cell	a 5.47556 · b 5.47556 · c 7.35685 Å · α 90° · β 90° · γ 120°
Transition	3.2 K (−270 °C)
Measured at	1.5 K
Magnetic ions	Fe
Largest moment component	3.81052 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 P31′(1/3,1/3,γ)ts →

Atom sites · 10 sites · CSV

site	element	x	y	z
Ag1_1	Ag	0.3333	0.6667	0.2815
Ag1_2	Ag	0.6667	0.3333	0.7285
Rb1_1	Rb	0	0	0
Fe1_1	Fe	0	0	0.5
V1_1	V	0.3333	0.6667	0.73
V1_2	V	0.6667	0.3333	0.27
O1_1	O	0.6681	0.913	0.6583
O1_2	O	0.3319	0.087	0.3417
O2_1	O	0.3333	0.6667	0.9591
O2_2	O	0.6667	0.3333	0.0409

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

N. E. Amuneke et al. Chem. Mater. (2014) · doi:10.1021/cm5025712

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 1.1.100_RbAg2Fe(VO4)2.mcif from MAGNDATA · entry page

sha256 of this copy: eb290873f204550028e3627c1d074b19e80101c663bac833fffdf7e65e1efbca
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 1.1.100_RbAg2Fe(VO4)2.mcif.