Research/Sitter/MAGNDATA / 1.1.111_MnO2.mcif

MnO₂

MAGNDATA entry 1.1.111 · 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 ≤ 93 K (−180 °C)Colour: where that sits relative to 25 °C. Saturation: how much margin it has.

Structure · 10 properties

Magnetic group	P4₂2₁21′(0,0,γ)-q00s
Point group	4221′
Parent space group	P 4₂/m n m No. 136
Repeats every	3.37 cells along c (not a whole number: that's what incommensurate means)
Propagation	[0 0 0.297] 1k
Cell	a 4.4041 · b 4.4041 · c 2.8765 Å · α 90° · β 90° · γ 90°
Transition	93 K (−180 °C)
Magnetic ions	Mn
Largest moment component	1 μ_B
Method	XRSC

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 P4₂2₁21′(0,0,γ)-q00s →

Atom sites · 2 sites · CSV

site	element	x	y	z	m_a	m_b	m_c	\|m\| (μ_B)
Mn1	Mn	0	0	0
O1	O	0.3046	0.3046	0

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

H. Sato et al. Journal of the Physical Society of Japan (2001) · doi:10.1143/JPSJ.70.37

Cite the original paper and MAGNDATA, not this mirror.

Original file

⬇ 1.1.111_MnO2.mcif from MAGNDATA · entry page

sha256 of this copy: 1bf07fd9aa4106a20d9fd231478cb4a0d19b3db922ef502b4624bfad1c50297f
The mirror keeps the bytes Bilbao served, so the original should hash the same unless MAGNDATA has revised the entry since: shasum -a 256 1.1.111_MnO2.mcif.