Research/Sitter/MAGNDATA / 0.507_Mn4Nb2O9.mcif

Mn₄Nb₂O₉

MAGNDATA entry 0.507 · 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 ¹3̄¹m × ²1: each symmetry marked ¹ keeps every spin, ² swaps up and down.

ordered ≤ 125 K (−148 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 10 properties

Magnetic group	P 3′ c′ 1 BNS 165.94
Parent space group	P 3 c 1 No. 165
Spins	collinear · net moment 0 μ_B per cell
Propagation	[0 0 0] 1k
Cell	a 5.335 · b 5.335 · c 14.32 Å · α 90° · β 90° · γ 120°
Transition	125 K (−148 °C)
Measured at	4.2 K
Magnetic ions	Mn
Largest moment component	5.9 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 3′ c′ 1 →

Atom sites · 5 sites · CSV

site	element	x	y	z	m_a	m_b	m_c	\|m\| (μ_B)
Mn1	Mn	0.3333	0.6667	0.0181	0	0	5.9	5.9
Mn2	Mn	0.3333	0.6667	0.297	0	0	5.9	5.9
Nb1	Nb	0	0	0.3575
O1	O	0.3	0	0.25
O2	O	0.334	0.295	0.0884

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

E. Bertaut et al. J. Phys. Chem. Solids 21(1961)234. (1961) · doi:10.1016/0022-3697(61)90103-2

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 0.507_Mn4Nb2O9.mcif from MAGNDATA · entry page

sha256 of this copy: cdeac7084f7057a4ccd58db8cd11163ff94ee940303e7fee2be0ec94cbaa6798
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 0.507_Mn4Nb2O9.mcif.