MAGNDATA - Collection of Magnetic Structures

MAGNDATA

Collection of Magnetic Structures

MAGNDATA: A Collection of magnetic structures with portable cif-type files

Magnetic structure with all atoms

Magnetic structure with only magnetic atoms

Reference: M. Melamud, H. Pinto, J. Makovsky, H. Shared, phys. stat. sol. (b) (1974) 63 699 - 707
DOI: 10.1002/pssb.2220630234
Atomic positions from: ICSD #27511

Parent space group (paramagnetic phase): P6₃/mmc (#194)
Propagation vector(s):
k1 (1/3, 1/3, 0)
k2 (0, 0, 0)

Transition Temperature: 21.5 K
Experiment Temperature: 4.2 K

Lattice parameters of the magnetic unit cell:
12.47410 12.47410 6.03150 90.00 90.00 120.00
Transformation from parent structure: (-a-2b,2a+b,c;0,0,0)
    [View matrix form]

BNS Magnetic Space Group: P6₃'/m'cm' (#193.259) (standard setting)
    [View symmetry operations]
Transformation to a standard setting: (a,b,c;0,0,0)
    [View matrix form]
Systematic absences for this Magnetic Space Group via

Magnetic Point Group: 6'/m'mm' (27.5.104)
    [View symmetry operations]
Symmetry-adapted form of material tensors via
Symmetry-adapted form of material tensors for domain-related equivalent structures via

Positions and magnetic moments of symmetry independent atoms:
From now on, magnetic atoms are in boldface and colored in red. Magnetic moments are expressed in units of μB

     [Show only magnetic atoms]                                             Use MVISUALIZE to:
     [Show all the atoms]

Label	Atom type	x	y	z	Multiplicity	Symmetry constraints on M	M_x	M_y	M_z	\|M\|
Co1_1	Co	0.00000	0.00000	0.00000	2	0,0,m_z	0.0	0.0	2.3(3)	2.30
Co1_2	Co	0.33333	0.66667	0.00000	4	0,0,m_z	0.0	0.0	-2.3	2.30

[Show all magnetic atoms in unit cell and their moment relations]

Active Irreps:

label	dim. full irrep	dim. small irrep	direction	action	number of modes	presence
mK3	2	1	special	primary	1
mGM4+	1	1		secondary	1	yes

Comments:

NPD and NSD
Position structure from another study at 293K
Moment magnitude is from the NSD. A quite different magnitude of 3.0(3) is reported for the fit of NPD data.

Comments (symmetry):

1k magnetic structure
k-maximal magnetic symmetry
2-dim irrep along a special direction as primary
A k=0 component (third harmonic) according to irrep mGM4+ is allowed by the MSG, and it is present in the model. This secondary contribution is necessary in order to have the same moment magnitude in the two symmetry independent Co sites, as considered in the model.
See #1.0.9 for another similar model of this structure, but with different moment magnitudes of the two independent Co atoms

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